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Help:Recent changes

Other languages: da, de

The Recent Changes page in MediaWiki lets you see the most recent edits made to pages in your MediaWiki project. Using this page, users can monitor and review the work of other users, allowing mistakes to be corrected and vandalism to be eliminated. There is a link to the Recent Changes page at the top of each page and in the sidebar of each page. You can also create a link to the page as Special:Recentchanges.

Understanding Recent Changes
With the default preferences, the bulk of the page consists of fifty lines, one for each edit, looking like this:
 * (diff) (hist) . . MediaWiki User's Guide: Editing mathematical formulae; 10:06 . . 128.214.14.50 (Talk) (Add examples)
 * (diff) (hist) . . N MediaWiki User's Guide; 10:06 . . Brion VIBBER (Talk) (New page)
 * (diff) (hist) . . Endnotes moved to Footnotes; 10:05 . . Maveric149 (Talk)

This indicates three edits: the first by a user who is not logged in, to MediaWiki User's Guide: Editing mathematical formulae; the second by Brion VIBBER to MediaWiki User's Guide; and the third by Maveric149 to Endnotes.

From left to right:
 * In a line showing the most recent edit to an page at the time of creating the Recent Changes list, the diff link shows the changes introduced by this edit, and also any edits that have taken place since the Recent Changes page was loaded. For other lines, it shows the changes in that edit only. The diff link is not available for new pages, or for page moves
 * The hist link corresponds to the Page history link on the edited page: it shows not just this edit but also older and newer ones. For page moves, the hist link leads to the history of the new page title
 * A bold m indicates that the user marked the edit "minor". Only logged in users can mark edits minor, to avoid abuse.
 * A bold N indicates that the page is "new", i.e., previously did not exist. It is possible for a change to possess both the "minor" and "new" indicators, this is typically used for new redirects.
 * The next link is a link to the current version of the page in question.
 * 10:06 refers to the time in UTC. You can change the time to your time zone using your preferences - see how to set preferences.
 * For logged in users, the next link is a link to their user homepage (as usual with internal links, the view page if the page exists, the edit page if it does not, the two being styled differently). For users who are not logged in, the link is to their User Contributions.
 * Finally, there is a link to the user's talk page (the same remarks regarding existence apply).
 * For page moves, a link is given to both the old and new title.

Preferences
Logged in users can set preferences to adjust the way that Recent Changes looks. For help in doing this, see how to log in and how to set preferences. The options that affect recent changes are:

 * Hide minor edits in recent changes - this hides all edits that have been marked as minor by logged in users;
 * Enhanced Recent Changes - with this option enabled, multiple edits are grouped together. This option uses JavaScript, and won't work in every browser (see Browser issues with MediaWiki). See MediaWiki User's Guide: The enhanced Recent Changes page
 * Number of recent changes. You may select the number of changes which will be shown by default on the Recent Changes page. Once on that page, links are provided for other options. In the case of Enhanced Recent Changes this number of changes includes those that are initially hidden.

Top of Recent Changes page
The content of Recentchanges is what appears at the top of Special:Recentchanges. It can be edited when necessary. Wikipedia talk:Recentchanges is for discussing what might go on it.

Viewing new changes starting from a particular time
If you have loaded the recent changes at, for example, 09:45 Feb 25, 2003, it gives a link "Show new changes starting from 09:45 Feb 25, 2003", giving you the changes you have not seen yet. In order to use this link later, after you have used the browser window for other things, or if you switch off the computer in between, you can instruct your browser to bookmark it (with Internet Explorer: right-click on the link and choose "add to favorites"). Alternatively, you can save the page with recent changes.

To get the new changes without one of these preparations, use (in this case, if the time above is UTC+1):

http://textbook.wikipedia.org/w/wiki.phtml?title=Special:Recentchanges&from=20030802064526

(format yyyymmddhhmmss, UTC time).

You can copy this URL to the address bar and change date and time.

The "Number of titles in recent changes" set as preference is applicable.

This feature can not be used in conjunction with "hide logged in users" (see below) unless the URL is modified manually.

Hiding logged in users from recent changes
Special:Recentchanges/hidelui is a version of recent changes that only shows changes by users who have not logged in. This can be useful for those watching out for vandalism. Features such as viewing changes starting from a particular time can be used with the hideliu feature, but only by manually altering the URL to add  &hideliu=1 to it. For example, clicking the time (as described in the section above) may take you to the URL
 * http://textbook.wikipedia.org/w/wiki.phtml?title=Special:Recentchanges&from=20030802064526

You would need to change this to read
 * http://textbook.wikipedia.org/w/wiki.phtml?title=Special:Recentchanges&from=20030802064526&hideliu=1

in order to view the recent changes without logged in users starting from this time.

Restriction on number of edits; alternatives
A maximum of 5000 edits can be obtained, currently on the English Wikipedia covering ca. 3 hours (use "limit=5000").

Checking changes for a longer period are restricted:
 * watched pages: use "My watchlist" in combination with "Revision history"). This runs less smoothly: on the English Wikipedia it often does not work ("database error" or "sorry, we have a problem").
 * pages that are linked from a given page (use "Related changes" in combination with "Revision history")
 * newly created pages (use "Newly created articles", then view the current version, or, if desired, also the revision history)
 * individual pages (use "Revision history") and individual users (use "User contributions" in combination with "Revision history").

See also below.

Edit records that are changed or lost
After a page has been renamed (moved), earlier edits, including the original creation of the page, are shown in Recent Changes etc. under the new name.

After a page has been deleted, earlier edits, including the original creation of the page, are not shown in Recent Changes etc.

In this Recent Changes differs from a real log of editing events (the latter in the sense that something that has happened can not be changed afterwards). Compare Historical revisionism.

However, some edit lines are in Recent Changes (as long as it lasts) but no longer in edit histories, watchlists, Related Changes or User Contributions: when moving a page over a redirect, the creation of that redirect is only in Recent Changes (and only if that was recent enough, of course). In particular this applies in the case of re-renaming a page back to its original name, and subsequent renamings back and forth.

Bots
Bots can be hidden from recent changes by adding &hidebots=0 to the url. It is possible for sysops to mark some edits as bot edits, thereby preventing them displaying in the default recent changes. See en:Wikipedia:revert for more information on this.

Other MediaWiki features showing lines about edits
(see also en:Wikipedia:Edit_summary).

Revision history (also called page history)
Every line represents one edit to the given page and the version resulting from it
 * "last" is similar to "diff", explained above
 * "cur" gives the difference between this version and the current one (i.e., excluding the edit shown by pressing the "last" next to it), which is the cumulation of all later edits, including those which are not in this revision history because they were made after loading this page
 * the date and time link to the version of that day and time, except that in the first line, which is about the latest edit at the time of loading this revision history, the date and time link to the current version, hence with the changes made after this revision history was loaded;

The "cur" and "last" features are similar to those in Enhanced Recent Changes, except for "cur" in the first line: it is not linked in the revision history, while in the Enhanced Recent Changes it gives the differences corresponding to the last edit; just after loading the revision history this is the same as the "cur" link of the second line gives, but if there have been edits after loading it is different.

title: Help:Recent changes


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Help:Printable

If you use the default skin ("Monobook"), MediaWiki uses Cascading Style Sheets in order to specify the style and layout of the printable version of a page. In modern browsers, the print function of the browser should automatically select this style sheet when you print an article -- hence the "Print" command of your web browser is normally all you need to know.

If you are using other, older skins such as the "Standard" skin, you can get a printable version of a page using the "Printable version" link, or by adding the text "&printable=yes" to the URL, e.g.

http://meta.wikimedia.org/w/wiki.phtml?title=Help:Template&printable=yes

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Help:Printable


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Help:Searching

This page explains how to search the wiki for what you are looking for.

Search facilities in MediaWiki
This page explains the search button for the search box which appears on every page. and the "Search result settings" section in the preferences.

list of all pages

 * Special:Allpages - Alphabetic index for the main namespace

Please note that a-z come after A-Z.

For some other namespaces, see Help:Namespace.

Go button
See also Help:Go button.

Search field
Pressing the [Enter] key while the search field is active is equivalent to clicking on the [Go] button. While this is obvious when using Internet Explorer (tested on version 6), Mozilla (version 1.6 at least) provides no such indication.

Avoid short and common words
This is the most likely cause of an unexpected failed search. If your search terms include a common "stop word" (such as "the", "one", "your", "more", "right", "while", "when", "who", "which", "such", "every", "about", "onto"), then your search will fail without any results. Short numbers, and words that appear in half of all pages, will also not be found. In this case, drop those words and rerun the search.

See Help:Common words, searching for which is not possible for the stop words filtered out by the database. From there one can at least go to a page with a stop word as title. Searching for the combination of one or more words and the common word "not" give a database query syntax error due to a bug in the software.

Search is case-insensitive
The searches for "fortran", "Fortran" and "FORTRAN" all return the same results.

Boolean search possible
You can use the words "and", "or" and "not" and parentheses in order to formulate more complicated requests. If none of those words is specified, "and" is used by default. For instance, "indian not american" will return all pages that contain the word "indian" but don't contain the word "american". The search "(Adolph or Adolf) and Hitler" will return all pages which contain "Hitler" and either "Adolf" or "Adolph".

Words with special characters
In a search for a word with a diaeresis, such as Sint Odiliënberg, it depends whether this ë is stored as one character or as "&euml;". In the first case one can simply search for Odilienberg (or Odiliënberg); in the second case it can only be found by searching for Odili, euml and/or nberg. This is actually a bug that should be fixed -- the entities should be folded into their raw character equivalents so all searches on them are equivalent. See also MediaWiki User's Guide: Creating special characters.

phrase
To search for a phrase, enclose it in double quotation marks.

No regular expressions or wildcards
You cannot use regular expressions or wildcards such as ? or *. If you don't know what that is, don't worry about it. To search for pages with the words "boat" or "boats" search like this: "boat or boats".

Words in single quotes
If a word appears in an page with single quotes, you can only find it if you search for the word with quotes. Since this is rarely desirable it is better to use double quotes in pages, for which this problem does not arise.

An apostrophe is identical to a single quote, therefore Mu'ammar can be found searching for exactly that (and not otherwise). A word with apostrophe s is an exception in that it can be found also searching for the word without the apostrophe and the s.

Delay in updating the search index
For reasons of efficiency and priority, very recent changes to pages are not always immediately taken into account in searches.

Namespaces searched
The search only applies to the namespaces selected in the preferences. To search the other namespaces check or uncheck the tickboxes in "Search in namespaces" box found at the bottom of a search results page. Depending on the browser, a box may still be checked from a previous search, but without being effective any longer! To make sure, uncheck and recheck it.

Searching the image namespace means searching the image descriptions, i.e. the first parts of the image description pages, and the titles, but only of those images which have an image description!

The URL is

http://meta.wikimedia.org/wiki/Special:Search?ns0=1&ns1=1&ns2=1&ns3=1&ns4=1&ns5=1&ns6=1&ns7=1&ns8=1&ns9=1&ns10=1&ns11=1&ns12=1&ns13=1&ns14=1&ns15=1&searchx=Search&limit=100&search=qqq

where "qqq" is used as example for the search term, and 1's can be changed into 0's for excluding namespaces.

Thus, e.g.

http://meta.wikimedia.org/wiki/Special:Search?ns0=0&ns1=0&ns2=0&ns3=0&ns4=0&ns5=0&ns6=0&ns7=0&&ns9=0&ns10=1&ns11=1&ns12=0&ns13=0&ns14=0&ns15=0&searchx=Search&search=test

searches the Template and Template talk namespaces for "test", and

http://meta.wikimedia.org/wiki/Special:Search?ns0=0&ns1=0&ns2=0&ns3=0&ns4=0&ns5=0&ns6=1&ns7=0&&ns9=0&ns10=0&ns11=0&ns12=0&ns13=0&ns14=0&ns15=0&searchx=Search&search=jpg

searches the image description pages for "jpg".

(Also there is a special search feature Special:Imagelist, which searches in titles, regardless of whether there is an image description.)

Searching with the URL above does not work if the search term exists as a pagename in any namespace!

Redirects can be excluded
Check or uncheck the tickbox "List redirects" in "Search in namespaces" box found at the bottom of a search results page.

The wikitext is searched
The wikitext (source text, what one sees in the edit box) is searched. This distinction is relevant for piped links, for interlanguage links, special characters (if ê is coded as &ecirc; it is found searching for ecirc), etc.

Secondary search
After finding the pages, these pages are searched again to have the results show in red in the context lines; this search uses a more relaxed criterion: search terms occurring in the wikitext, even as part of a word, are shown in red.

Oddly, sometimes no context is shown.

Google
The URL
 * http://www.google.com/search?q=site%3Awikipedia.org+%22interwiki+link%22

searches for the phrase interwiki link in wikipedia.org — that is, in all Wikipedias as well as Wikisource (sources.wikipedia.org) and meta.wikipedia.org, but not meta.wikimedia.org.

%3A is a colon, %22 a double quotation mark ("), and + is equivalent to a space ; %20 may also be used for a space. (See also Help:URL.)

Note that the underscore (_) is not equivalent to a space: putting it in the URL results in a search for a word containing actual underscores at those positions. Thus
 * http://www.google.com/search?q=site%3Awikipedia.org+%22interwiki_link%22

finds pages containing the term interwiki_link.

Administration Options
from includes/DefaultSettings.php, apperantly you have to look up your namespace table, because they are numbered...

$wgNamespacesToBeSearchedDefault = array( -1 => 0, 0 => 1, 1 => 0, 2 => 0, 3 => 0, 4 => 0, 5 => 0, 6 => 0, 7 => 0, 8 => 0, 9 => 1, 10 => 0, 11 => 1 );

I would guess that -1 is the default settings.. and 0 is main namespace.. and 0 is off and 1 is on.

title: Help:Searching


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Help:Starting a new page

Other languages: English, Danish, German, Esperanto, Spanish, Indonesian, Italian, Dutch,  Chinese, Tok pisin

A new page is distinguished from a blank page: the latter has a page history. However, creating a new page is just like editing a blank page, except that the message that is in MediaWiki:Newarticletext appears, which can be different per project.

For general editing matters, in particular the markup language of the wikitext, see Help:Editing.

General principles

 * Search to see whether someone has written a similar page before you start one yourself.
 * Review conventions of the project you are working in regarding e.g.:
 * the naming; see also Help:Page name.
 * whether a separate page is justified; perhaps it is better to add the text to a related page (especially if the text is not very long); that page can always be split later, after it has grown.

Starting a page from an existing link, after creating one, or after a search
To start a new page, you can start from a link to the title of the new page. On the English Wikipedia, due to w:MediaWiki:Nogomatch, another way is to perform a search (as you should have done before) with the Go button and coming up with nothing, pressing "create the article".

Internal links to non-existing pages are typically created in preparation of creating the page, and/or to encourage other people to do so. Typically they look different from links to existing pages, depending on settings: a different color or with a question mark (sometimes they are called "red links" after one of the default settings).

Such a link is to the edit mode of the non-existing page, which allows creating it, just like editing a blank page.

Before following the edit link, decide whether you want to give the new page the suggested name. If not, first edit the link on the referring page.

Of course you can also create the link yourself, in a related page or index page. However, it may be better to wait with creating links until after creating the new page, especially if the link would replace one to an existing page. In that case you can create the link but just press Preview, not Save (a previewed link also works) or create the link first only on your user page.

Note that links on related pages are not only convenient for navigation, but also make people aware of the new page (those who happen to read a related page, but also those who watch such a page).

Starting a page through the URL
The URL corresponding to a non-existing page gives a webpage like that of an existing page, showing the text that is in MediaWiki:Noarticletext. Note: This is really confusing!

It has the usual edit link, which allows you to create the page.

Thus a "broken link" from within or outside the project is, in a way, not really broken, as long as the first part of it is correct.

An easy way to produce the URL is editing the last part of the URL of another page in the same project.

An interwiki link to a non-existing page (not recommended) gives the same result.

To get access to a MediaWiki project with all the links at the edges, but without superfluous loading of any page, you can bookmark a non-existing page.

Creating an empty page
Occasionally it is useful to create an empty page. For example a template can be made such that, depending on a parameter, it produces either just a standard text or also an additional text. This is done by having it call another template, of which the name is a parameter; one version of the other template contains the additional text, the other version is blank.

A blank page cannot be created directly; first create a non-blank page, e.g. with just one character, then edit the page to blank it.

title: Help:Starting a new page


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Help:Watching pages

Anyone may choose to be notified when a certain page changes using "watch" and "my watchlist". MediaWiki doesn't let people "own" pages, however, this feature and the ability to revert pages, provides the most needed functionality--without the drawbacks of giving somebody absolute control over a page.

Use
When logged in, users should see a link in the sidebar entitled "Watch this page" on non-dynamically-generated pages. By clicking on that link, you add the current page and the corresponding Talk page (or if it is a Talk page, that page and the corresponding article page, etc.) to the collection of articles you "watch". You can access your watchlist by clicking the "My watchlist" link in the sidebar or choosing "My watchlist" from the "Special pages" menu at the top of each page and pressing "Go". Your watchlist approximately functions as a custom recent changes just for articles that you watch. It gives a list of all watched pages, ordered backward according to the time of the last edit of the page, optionally up to some cutoff time.

The default cutoff for the watchlist is currently three days for users with less than 1000 pages in their watchlists and 12 hours for Wikipediholics with more than 1000.

Each line shows details about the last edit: the day, whether minor or major, the time, a link to the article, the difference between the current version and the last but one, the history, the user name and the edit summary. There is currently no way to exclude minor changes from the watchlist.

Note that for every edited page only information about the last edit is shown. For example, if the last edit was minor there is no indication whether there have also been major changes recently. Since one is typically interested in all changes since one last checked, the history of the article needs to be checked.

In Recent Changes and Enhanced Recent Changes, watched articles are bolded. Therefore, even without ever using "My watchlist", specifying articles to watch is useful.

Deletion of pages
Oddly, the deletion of a watched page is not shown in the watchlist!

Watching and unwatching
There's a handy "watch this page" or "stop watching this page" link in the sidebar when viewing any Wikinews page while logged in.

Users can also specify that a page must be watched while editing that page:

On the editing screen, next to the minor edit checkbox, there is another checkbox with the text "Watch this page". Activating this checkbox and saving the article produces the identical result to clicking the link mentioned above. When viewing a watched page, the "Watch this page" link text changes to "Stop watching". Clicking that link removes the page and its talk page from your watchlist. Deactiving the checkbox "Watch this page" before saving an article has the same result.

Furthermore you can activate the user preference "Add pages you edit to your watchlist".

If you find after a while that you've got a lot more pages watched than you want, there's a handy link at the top of the Watchlist which will display your entire watchlist in alphabetical order. From there you can remove pages en masse by doing a lot of clicking of checkboxes.

Keeping a number of separate watchlists
Pages with links (possibly specially created for this purpose, e.g. as subpages of one's user page) can be used with Related Changes as a collecting of separate "watchlists".

Css
As an alternative or in addition to using the watchlist feature, one can also define a user style for links to selected pages, putting in one's CSS a list of lines like:

 * a[title ="pagename"] {color: white; background: red; font-size: 150% }

This works in Opera, but not in IE.

On the (Enhanced) Recent Changes page it works like the bolding feature mentioned above, but it is more versatile, e.g. allowing extra emphasis on pages one is very interested in, or different styles for different categories of interesting pages. Furthermore, it also works on user contributions pages, and on regular pages (also for piped links, but not for indirect links through a redirect). It also applies, less usefully, for the section editing links in the page itself.

To highlight links to the given page also from other websites, including interlanguage links, use instead of the above:

 * a[href ="full url "] { .. }

Note that the full url is needed, even to highlight links from the same project, although the html code uses the relative url /wiki/pagename.

title: Help:Watching pages


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Help:Navigational image

In projects that allow embedding images in external link style (in which case you see three images in the lefthand side of the table below), the image can also be external, and the target can be any URL; there are the following possibilities:

Thumbnail
One application is linking a small version of an image to a large one. Example where both are external:

http://pennine.demon.co.uk/photos/seakayak/small/Lunga-P7-100-3086.jpg

gives

http://pennine.demon.co.uk/photos/seakayak/small/Lunga-P7-100-3086.jpg

The alternate text is the name of the image, after the last slash in the URL. If you have control over the image, give it a meaningful name; you could even include a text like "click to enlarge" in the name.

title: Help:Navigational image


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Help:Page history

The revision history, also called page history or edit history, of all pages is available. It consists of the old versions, and also a record of the date and time of every edit, the user who made it, the edit summary, and a possible marking as "minor edit".

Page history
An exception are pages which have been deleted (not to be confused with paged that have been blanked), the only record available for non-administrators is the deletion log and possibly the "votes for deletion" archive. Edits to them are not even in the User Contributions pages. However, the revision history is kept and can be retrieved by a sysop, who can also undelete the page (see en:Wikipedia:Viewing and restoring deleted pages by sysops.

The policy of keeping the page history did not exist in the beginning of Wikipedia's existence, so the page history of that time is lost.

Every page has a link "Page history" to the list of edits. Also the Recent changes and Related changes pages have links to the histories of listed pages.

Every line represents one edit to the given page and the version resulting from it
 * "last" is similar to "diff", explained in Recent changes
 * "cur" gives the difference between this version and the current one (i.e., excluding the edit shown by pressing the "last" next to it), which is the cumulation of all later edits, including those which are not in this revision history because they were made after loading this page
 * the date and time link to the version of that day and time, except that in the first line, which is about the latest edit at the time of loading this revision history, the date and time link to the current version, hence with the changes made after this revision history was loaded;

The "cur" and "last" features are similar to those in Enhanced Recent Changes, except for "cur" in the first line: it is not linked in the revision history, while in the Enhanced Recent Changes it gives the differences corresponding to the last edit; just after loading the revision history this is the same as the "cur" link of the second line gives, but if there have been edits after loading it is different.

For every version there is a box on the line. Marking two boxes gives the difference between the two versions. The box at the top corresponds to the latest edit, which is not necessarily the edit about which the info on the line is (another edit may have been made after loading the page history),

If the "move page" feature has been used in the past to change the name to the current one, the entire edit history of the article, before and after the move, is shown, but the move itself is not. The move itself is shown in the edit history of the page with the old title, which automatically has become a redirect page.

.

Special:Export
Through Special:Export the source text of the current and old versions of a page, with the info in the page history lines, can be packed together in a single XML-file. Also for a list of pages all can be put in a single file. This also allows searching for a text in the collection of versions. See also XML export.

Image history
An "image" (in the broad sense of an uploaded file) can be edited, or, more generally, be replaced by a different image, by uploading a new image file with the same name. Again all versions are kept. The image history listing forms part of the image description page, which appears when clicking on the image. The image history consists of this and the old versions themselves.

The image description page consists of three parts:
 * description of the image
 * "Image history"
 * "Image links"

The description part has also an edit history; it is labelled, somewhat confusingly, Image:xxx Revision history. It should not be confused with the Image history.

Not kept are images which have been deleted (not to be confused with images that are no longer used in articles), the only record available is the upload log, deletion log and possibly the "votes for deletion" archive. Neither the latest nor older versions are kept by the system, hence it is not possible to undelete an image.

Revision history of articles containing images or templates
The actual history of an article with images is the combined effect of the revisions of the source text, including references to images, and the revisions of the images themselves.

As a result:

 * Old versions of articles do not show corresponding old versions of images, but the latest ones, unless the file names of the images have changed.
 * Changes in images are not shown in the page history of the article if the same image name was used.

Similar remarks apply for templates.

Archiving
Archiving texts in separate pages is superior to using the page history as archive: texts in archive pages can be found searching with Google and using the search feature of Wikipedia. Page histories can only be searched after applying Special:Export. Also, archive pages can be organized and titled afterwards in a suitable way, while e.g. edit summaries can not be supplied afterwards. However, an index of old versions of a page, with links to them, could be prepared.

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title: Help:Page history


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Help:Page name

Special characters
The following characters are not allowed in page titles:

" # $ * + < > = @ [ ] \ ^ ` { } | ~

The reasons include:

 * + is used in web addresses to represent a space (e.g. when you type more than one word into a search engine). Using it in article names would potentially make parts of the system see their name wrong. Each + will be substituted by ' ' (space) respectively '_' (underscore) in the related page URL, see below.
 * @ also has a special meaning in URLs, as a way of adding a username and password, and would have even more drastic consequences.
 * [, ], {, }, |, and probably some of the others have special meaning within Wikipedia's syntax, which are processed before the pagename is determined. (e.g. 2024 points at 2024, not a page called  2024 .
 * $, \, ", ` (and some others) have special meaning in other bits of the software, and allowing them would create potential security flaws which would take a lot of effort to insure against.

There are some pages not satisfying the restrictions, e.g. $. They may give complications.

Some very special characters, like two dots over the n that has been attempted for the page Spinal Tap, are not allowed either. They can only be represented using Unicode, whereas the English Wikipedia just uses ISO 8859-1 or similar.

Namespace prefixes
Also, the first part of a page name may not coincide with a project-independent namespace prefix that is automatically converted to another one, e.g. the name Project: A-Kon on Wikipedia is not possible.

The first part of a page name can coincide with a namespace prefix that is not converted. For example, there might be articles in the English Wikipedia about books called Wikipedia: The Big Adventure and Talk: Secrets are Bad (but only without the space after the colon). However, in that case the pages are in the wrong namespace. This may be inconvenient in searching or displaying a list of pages. Also, in the second case there is no link to a Talk page about the book. (As explained above, the second page name is not possible on e.g. the German Wikipedia: see w:de:Talk: Secrets are Bad).

Prefixes referring to other projects or pseudo-namespaces
A page name can not start with a prefix that is in use to refer to another project, including language codes, e.g. "en:" (list), or one of the pseudo-namespaces "Media:" and "Special".

Spaces vs. underscores
In page names, a blank space is equivalent with an underscore. A blank space is displayed in the large font title at the top of the page, the URLs show an underscore. See also below.

Case-sensitivity
If for the first letter of a page name two cases exist, as in the case of letters of the Latin, Greek, Cyrillic, and Armenian alphabets, the following applies.

All characters of namespace prefixes are case-insensitive. The canonical form, shown in large font as page header, and in URLs generated by the system, is with one capital. Below "page name" refers to the name without the possible namespace prefix.

Case-sensitivity of the first character
The first character of the page name may or may not be case-sensitive, depending on the project. Help:page name gives on this project: Help:page name. If the first character of the page name is case-sensitive this is a link (to a different page), otherwise it is bold (a self link to this page).

Currently in all Wikimedia projects other than the Klingon Wikipedia and the toki pona Wikipedia it is not. For these two, compare e.g. jo and Jo, and w:tokipona:musi with w:tokipona:Musi. For Wiktionary changing this is being discussed at Wiktionary:Wiktionary:Beer parlour/case-sensitivity vote.

Case where the first character is case-insensitive
The canonical form is with a capital. A link like template works like a piped link template : template; unlike a redirect, the conversion shows up already on the referring page when pointing at it: in the pop-up and in the status bar (if applicable for the browser).

Note that in the case of a prefix that is not a namespace for the software, and in the case of a second prefix, the case-insensitivity does not apply to the first character after this prefix, e.g. Template:H:Interwiki linking and Template:H:interwiki linking are distinguished.

Case-sensitivity of the file name extension of an image
Note that even the file name extension of an image is case-sensitive: compare File:Stop sign us.jpg and File:Stop sign us.JPG

Ignored spaces/underscores
Spaces/underscores which are ignored:
 * those at the start and end of a full page name
 * those at the end of a namespace prefix, before the colon
 * those after the colon of the namespace prefix
 * duplicate consecutive spaces

Some show up in the link label, e.g. ___help__ :_ _template_ _ becomes ___help__ :_ _template_ _, linking to Help:Template.

However, a space before or after a "normal" colon makes a difference, e.g. MediaWiki User's Guide: Editing overview and MediaWiki User's Guide : Editing overview, and MediaWiki User's Guide:Editing overview are all distinguished, because "MediaWiki User's Guide:" is a pseudo-namespace, not a real one.

Coding of characters
A page name can not contain e.g. %41, because that is automatically converted to the character A, for which %41 is the code. %41 is rendered as %41. Similarly %C3%80 is automatically converted to the character À. %C3%80 is rendered as %C3%80. The URL of the page is http://meta.wikipedia.org/wiki/%C3%80. One can argue what is the real name of the page, %C3%80 or À (a user will say the latter), but anyway there can not be distinct pages with these names.

Alphabetical order
Alphabetical order, e.g. in Special:Allpages, is (at least for that range) according to ASCII. Note that this means that "a" comes after "Z", see e.g..

Variables and
Variable gives for this page, Variable  gives.

Thus in the first case a space is used, in the second case an underscore, like in URLs. Similarly À becomes the escape code %C3%80 (see above), etc.

For a page in the main namespace the page name is prefixed with a colon.

Example:

http://meta.wikimedia.org/w/wiki.phtml?title=Special:Whatlinkshere&target=:

gives

http://meta.wikimedia.org/w/wiki.phtml?title=Special:Whatlinkshere&target=:

would not work.

With a Google search there is the problem that for Google the space and the underscore are different, see w:Template talk:Google.

title: Help:Page name


text:
Help:Interwiki linking

By adding a prefix to another project, internal link style ("prefixed internal link style") can be used to link to a page of another project. For example,  links to the work The Elements of Style on Wikisource. This is called interwiki linking. Although certain sites can be linked to using this method even if they don't use MediaWiki or are not wikis, Wikinews convention forbids external links such as these in the body of an article in favor of an external links section if necessary.

When linking to other projects, it is also possible to use the templates w or wikt, and this is strongly recommended for linking to the English Wikipedia and English Wiktionary, respectively. Please see those templates for documentation on them.

Interwiki linking from and within Wikimedia
Within Wikimedia, for the purpose of interlanguage links (see below) the project families are Wikipedia, Wiktionary, Wikiquote, Wikibooks and Wikisource. Thus this applies for a link like en:, de:, etc., from a Wikipedia to another one, from a Wiktionary to another one, from a Wikiquote to another one, from a Wikibooks to another one or from a Wikisource to another one.

The interlanguage link feature works on Commons, and produces links to the Wikipedias. This is not reciprocal: a link from a Wikipedia to Commons is an in-page link.

Project titles and shortcuts
{| class="wikitable" ! Project !! Long form !! Shortcut Some prefixes work only with a page, e.g. (fails) vs. Interwikimedia link (works). These prefixes are case insensitive.
 * Wikipedia
 * Wiktionary
 * Wikinews
 * Wikibooks
 * Wikiquote
 * Wikisource
 * Wikispecies
 * Wikimedia Foundation
 * Wikimedia Incubator
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * Wikibooks
 * Wikiquote
 * Wikisource
 * Wikispecies
 * Wikimedia Foundation
 * Wikimedia Incubator
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * Wikisource
 * Wikispecies
 * Wikimedia Foundation
 * Wikimedia Incubator
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * Wikispecies
 * Wikimedia Foundation
 * Wikimedia Incubator
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * Wikimedia Foundation
 * Wikimedia Incubator
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * Wikimedia Incubator
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * MediaZilla
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.
 * for the English Wikipedia working from any Wiki supporting the Meta Interwiki map, not only from MediaWiki Wikis.

One-letter prefixes (as a live check on the table):

Technical
A project's own namespace prefix cannot be reused as code for an external project. However, the prefix used for a target project may coincide with the prefix for a project namespace within that project. As a result, to link to a page in that namespace, use the same prefix twice, e.g..

For portability across projects, one may want to select a link code that leads to the same target from all projects, e.g. MetaWikipedia:wikibooks:Main Page. The "superfluous" "MetaWikipedia:" prevents "wikibooks:" being interpreted as namespace prefix when the code is used at wikibooks itself, while at Meta the "MetaWikipedia:" is ignored (it is not a namespace prefix, and even at Meta itself it is recognized as code for Meta). The codes above work from all projects. However, the existence detection and the self-link feature do not work on interwiki links.

Prefixes
Interwiki links can use prefixes for the project and/or for the language. Without prefix links are local, for pages in the same project and the same language. If only a language is given they go to a page in the same (or similar) project for the specified language:

fr: fr: os: os:

If only the project is specified they typically go to the language of the source, see above. At most two prefixes are needed for pages in any existing project and any supported language:

Hauptseite Hauptseite Main page   Main page

In the case of more than one prefix a page name has to be specified. For example, while and en: from Meta lead to the English Wikipedia's main page, a bare   does not work:. If the language is different specifying it before the project can also work:

de:q:Hauptseite de:q:Hauptseite en:n:Main page   en:n:Main page Main page   Main page

The second example doesn't work from English Wikipedia  pages, a project prefix before the language is better. More than two prefixes are generally unnecessary. The following examples should work everywhere:

m:Help:Help m:Help:Help Interwiki Interwiki

Two prefixes can have unexpected effects, e.g. from Meta the following links end up on different pages:

About   About en:m:About en:m:About About     About

In the first case Meta ignores the, because it's local, and then interprets as  prefix for the English Wikipedia. In the second case the leading  goes to the English Wikipedia, where the following   goes straight back to Meta. The second example doesn't work at all from English Wikipedia  pages, only the third example works everywhere.

In other words multiple prefixes are evaluated left to right by the relevant Wikimedia servers (project and language). For projects without different languages like Meta (because Meta is multilingual by itself) language prefixes can be handled as shorthands for  plus the specified language:

pl:2006   pl:2006 2006   2006 pl:w:2006 pl:w:2006

From Meta the first two links both arrive at the Polish 2006 page. The third arrives at the English Wikipedia, because that's how the server selected by  interprets the second prefix .

For a portable link on that server it would be a bad idea to use , but  does the trick. To test that effect from Meta the following links should go to the same page:

ja:2006    ja:2006 2006 2006

Wikia
In Wikia, the prefix is the internal project name for some older wikis. For others, "Wikia:c:" is added in front (e.g. [[Wikia:c:psychology]] or shorter [[w:c:trains:locomotive]] ).

From Wikimedia projects use [[wikiasite:psychology]] giving psychology, [[wikia:trains:locomotive]] giving wikia:trains:locomotive, or, for the central Wikia, About Wikia.

Interlanguage link
For a multilingual family of similar projects, with one project per language, a system for interlanguage linking can be set up, setting $wgInterwikiMagic to true, and $wgHideInterlanguageLinks to false. If this project is in a family for which this applies, Help:Interlanguage link demo may demonstrate what is explained below (this depends on whether the same language codes are used).

An interwiki link within the family is treated differently (unless it is on a talk page of any namespace): it appears at one or two edges of the webpage (left in Monobook, and top and bottom in Classic). The link label depends only on the sister project that is linked to, not on the linked page. The label is set in the configuration of the project. Typically, it is the name of the language written in that language. The target is only shown in the status bar, depending on the browser (oddly, there is not even a hover box).

Thus, interlanguage link is mainly suitable for linking to the corresponding page in another language. It is not suitable for multiple links of the same other language. See Interlanguage use case for a discussion of common troubles with this system and other possible implementations.

The feature can also be used on an image description page to link to the same or a similar image in a sister project. Other interwiki links to images require the prefixed colon.

Note that, if a page may be used as a template (even if it is not in the template namespace), it should note its interlanguage links between <noinclude> and </noinclude>. This is the same idea as for categories. Comparison: [[en:link]] without leading colon adds an interlanguage link to the page. <noinclude>[[en:link]]</noinclude> ditto limited to actual page.
 * 1) [[:en:link]] or [[:category:name]] are ordinary links.
 * 2) [[m:en:link]] or [[m:category:name]] are Interwiki links, see above.
 * 3) [[category:name]] without leading colon adds a category to the page.
 * 1) <noinclude>[[category:name]]</noinclude> limited to actual page.

For projects like Meta a missing leading colon has no effect, Meta doesn't support Interlanguage links. For Wikipedia and similar projects it's a major difference.

The mutual order of interlanguage links is preserved, but otherwise the positions within the wikitext are immaterial, again the same rule as for categories. Usually they are put at the end. With section editing they appear in the preview if they are in the section being edited.

A link to the project itself (hence also a link to the page itself), even if referred to with the project prefix, appears in-page.

Suppose that we have pages de:Zug, en:Train, fr:Train then we need:
 * on de: en:Train, fr:Train
 * on en: de:Zug, fr:Train
 * on fr: de:Zug, en:Train

Thus there is no possibility of simply copying each list, let alone of using a template, as can be done if different languages share one project, with or without separate namespaces, see e.g.:
 * Template:H-langs:Interwiki linking used at the bottom of this page on Meta
 * wikisource:Template:InterLingvLigoj
 * Template:About.

In-page interlanguage links
To make an interlanguage link in-page, prefix a colon (e.g. wiki ). This can e.g. be useful to link to a page in another language if no local version is available. See also some example templates, such as m:Template:Tiw, for conveniently making such links:

Interlanguage link in the wider sense
An interlanguage link in the wider sense includes a link to a corresponding page in another language which, for the software, is a regular link, as opposed to one employing the special interlanguage link feature as described above. This can also be an internal link on a multilingual project, e.g. on Meta:

 * Interlanguage links

Possible reasons for using an "interlanguage link" in the page body include:
 * control over position
 * control over label
 * the target contains an anchor

Interwiki links versus external links
Disadvantages of interwiki links:
 * the wikitext is less portable across wikis, because wikis do not always have an interwiki prefix for the same sites, and even if they do, the prefixes may differ
 * there is no feature to find interwiki links, while searching for an external link can be done with Special:Linksearch (if installed). This is due to the fact that, while there is an externallinks table, there is no such thing for interwiki links (the interwiki table only stores the interwiki prefixes with their targets as function of the parameter, not the instances of the links). Using the general text search to search for interwiki links is more work for the server, and therefore it may be slow, or not up-to-date, or in busy hours disabled. See also Finding external links to a page.

Using templates like h:mlw, the advantages of interwiki links and external links are combined. When a page using this template, which is in this case used for links to the English Wikipedia, is copied to that site, a template with the same name is needed there too. Due to that template, h:mlw, which redirects to h:ml, the interwiki links are automatically converted to internal links. Hence they provide existence detection, and allow use of "What link here" as well as Linksearch.

Interwiki links to the same wiki versus internal links
Disadvantages of interwiki links to the same wiki, compared to internal links: Advantages of interwiki links to the same wiki, compared to internal links:
 * no existence detection
 * "What links here" works for internal links only
 * better portability across wikis, provided that the same prefix applies, and is not equal to a namespace name

Using templates like h:ml, the advantages of internal links, interwiki links and external links are combined (with respect to portability: provided that a template with the same name and adapted content is present on the other site).

title: Help:Interwiki linking


text:
Help:Link

Linking from a page
The following types of hyperlink can be distinguished:

 * 1) internal link in internal link style (no class, class='stub', or class='new', see below)
 * 2) interwiki link in internal link style (class='extiw')
 * 3) link in external link style (class='external')

(the classes can be used for separate colors or fonts per class by means of a specification in a CSS)

If no link label is specified, 1 and 2 are of the form target_ (ctrl-click)"> target (with in case 2 target starting with a prefix) and 3 is of the form target, where target is the URL including "http://" ( ftp:// also works, but file:// does not). In case 3 no blank space is allowed in the URL. For MediaWiki pages the blank space can be replaced by an underscore, in general also %20 can be used; see also URLs in external links.

There are two ways of allowing the link label and the (eventual) link target to be chosen independently:
 * a label can be specified with in case 1 and 2 target_ (ctrl-click)"> label and in case 3 [ target label ], with a blank space in between, see Help:Piped link.
 * a page with the name of the link label redirects to the eventual link target.

In the first case the link title is the name of the (eventual) target page, in the second case it is equal to the link label. By using a piped link and a redirect, the label, title, and target can all be chosen independently, see also below.

Correspondingly, there are two ways to use an image as link to a page:
 * In the first method, only possible in projects that allow embedding images in external link style, an image plays the role of the label.
 * In the second method, the image description page contains a redirect.

In case 3, links like [ target ] are automatically labelled with serial numbers 1, 2, 3, ...

For link type 1 there is an existence detection feature: it will be a link to the viewing page if the page exists at the time of loading or previewing of the referring page (no class or class='stub'), otherwise to the edit page (class='new').

Stub feature
A link in internal link style to an existing internal page will be in class 'stub' iff all the following is true:
 * the page is in the main namespace
 * the page is not a redirect
 * the number of bytes of the wikitext is less than the value of the "threshold for stub display" specified in the preferences

The idea behind this is that such pages are "stubs" which need fixing, or which are less worthwhile to go to. Alternatively, with a higher threshold value, the feature allows indication that a page is large (with a slow connection perhaps a reason not to go to it). However, note that due to the possible inclusion of templates and images, a small wikitext does not necessarily mean a small composite page in terms of amount of information, or amount of bytes to load.

Also, by specifying a very high value as threshold, this feature allows, instead of the intended use of distinction according to size:
 * distinction according to namespace (in the main namespace or not); however, redirects in the main space are marked "as if in another namespace", regardless of the namespace of the target of the redirect
 * for links to the main namespace, known from the hoverbox or status bar, an indication of links having a redirect as target

However, linking to a section of what according to this criterion is a stub does not seem to work, except when external link style is used!

Miscellaneous
Reasons to use type 3 to link to an internal page or a page on a sister wiki include:

 * linking to the edit page of an existing internal page
 * linking to an edit page on a sister wiki (including a non-existing page, the link being an invitation or preparation for creating one, just like is common for internal pages)
 * linking to a page for which internal link style is not possible, such as an old version of a page, a diff of two versions, Recent Changes or Watchlist with parameters, Backlinks page, etc.

A redirect to a section of a page does not go to the section. One can use it anyway as a clarification, and at least it works when clicking on the link from the redirect page.

A link that specifies a section of a redirect page corresponds to a link to that section of the target of the redirect.

On some browsers, putting the mouse pointer over a hyperlink will show a hover box with the title attribute in the link anchor in the HTML code. This is the page name (without the possible section indication) in case 1, the page name with prefix in case 2, and the URL in case 3.

This can be switched off in the preferences. The browser may also show similar info, but with the possible section indication, in the address bar.

Plus sign in a link
In internal and interwiki link style, a plus sign in a page name is not allowed, the HTML and hence the rendered page just shows the wikitext, e.g. a+b. In external link style a plus sign in the URL is retained. It is often equivalent with a space. See also below.

Other conversions
In accordance with the rules explained in Help:Page name, conversions are made. This is demonstrated in the following examples:

__%20_%70RoJecT %20 : a   b   :  c __%20_%70RoJekT %20 : a   b   :  c

w:__%20_%70RoJecT %20 : a   b   :  c become links to http://meta.wikipedia.org/w/wiki.phtml?title=Meta:A_b_:_c_&action=edit http://meta.wikimedia.org/w/wiki.phtml?title=PRoJekT_:_a_b_:_c_&action=edit

http://en.wikipedia.org/wiki/pRoJecT_:_a_b_:_c_%23_d while in http://en.wikipedia.org/wiki/__%20_%70RoJecT_%20_:__a___b___:__c__#__d___%20 nothing is changed (except that when the browser reports the link target, %70 is converted to p).

Note that a project does not keep a record of namespace prefixes or capitalization settings of sister projects, therefore less conversions can take place in an interwiki link than in an internal link.

Linking to a page
A plus sign in the page name in the URL is equivalent with a space, e.g. /wiki/a+b leads to the page A b.

Apart from linking to the top, one can link to a section, see Help:Section. If one wants to link to a position that is not suitable for starting a (sub)section, one can not use a HTML element "a" (see Help:HTML in wikitext), but one can make a font or div tag like  or add id=".." to the start tag of any existing HTML element. See e.g. the three rank links in Netherlands and their targets.

If, on applying the link, the page name has to be converted, e.g. capitalized, then section linking still works, but the anchor part of the address disappears from the address bar. A consequence is e.g. that one can not conveniently bookmark the URL with anchor, after applying the link.

This is not applicable for internal links, because the conversions have already taken place on Preview or Save of the referring page.

Consider e.g.:

 * http://en.wikipedia.org/wiki/Wikipedia:How_to_edit_a_page#See_also
 * http://en.wikipedia.org/wiki/wikipedia:How_to_edit_a_page#See_also
 * http://en.wikipedia.org/wiki/Wikipedia:how_to_edit_a_page#See_also

The anchor part of the address disappears from the address bar in the 2nd and 3rd case.

Conversions:

http://meta.wikipedia.org/w/wiki.phtml?title=Meta:A_b_:_c_&action=edit

http://en.wikipedia.org/wiki/pRoJecT_:_a_b_:_c_#_d

http://en.wikipedia.org/wiki/__%20_pRoJecT_%20_:__a___b___:__c__#__d

lead to Meta:A b : c and twice to w:Wikipedia:A b : c

Link titles
As shown by the examples a, a, http://a.b#c, giving the link titles a, w:a, and http://a.b#c, respectively (also for the piped link versions), the anchor is in the title in the external link style, but not in the internal link style and not in the interwiki link style. However, even if the anchor is not in the title and even if the browser does not show the URL in the hover box, the anchor can still be seen in the status bar.

Since the HTML element "a" is disabled when put directly in the wikitext, one can not choose the link target and link title independently. This would be useful e.g. to link the word "inch" to the article "inch", with link title "2.54 cm", so that one gets informed through the hover box even without following the link. A workaround is to link to a page named "2.54 cm", which redirects to "inch".

Subpage feature
Depending on the project, for certain namespaces a subpage feature is enabled. On Wikipedia this is in talk namespaces, and the user and project namespace, on Meta also in the main namespace. The default set in DefaultSettings.php  is: $wgNamespacesWithSubpages = array(	-1	=> 0,	0	=> 0,	1	=> 1,	2	=> 1,	3	=> 1,	4	=> 0,	5	=> 1,	6	=> 0,	7	=> 1 );
 * 1) which namespaces should support subpages? See Language.php
 * 2) for a list of namespaces
 * 3) default: only discussion ("talk") namespaces and user pages
 * 4) allow subpages
 * 5) 0=no subpages, 1=subpages

Settings per project are done in LocalSettings.php.

A page with a name of the form A/b is considered a so-called "subpage" of the page A.

From the parent page it can be linked to with simply /b or the corresponding piped link. In namespaces for which the feature is disabled, the slash is ignored and not displayed. On this project in this namespace (Help) it gives: /b.

At the top of the subpage body a link to the parent page is shown automatically, without any corresponding wikitext. The link shows up even if the page A/b does not exist, provided that the page A exists.

Like most letters of a page name, the first letter after the slash is case-sensitive, A/B and A/b are different.

Subpages can have subpages themselves. Links to the whole hierarchy line of pages from the top is shown on the page.

What links here and Related changes ignore these automatic links.

See also w:Wikipedia:Subpages.

Additional effects of links

 * Related changes
 * Backlinks
 * Date format - since this effect applies for every link occurrence independently, a convention to avoid multiple linking to the same page within one page typically does not apply for date links.

title: Help:Link


text:
Help:Logging in

Logging in is not required for viewing pages, and not even for editing them. However, it provides additional features, and in general projects recommend it.

Logging in
Creating a user account means that you supply a username (your real name or a nickname) and a password. The system will reject a username that is already in use. A user account is created only once. You are then "logged in". Next time you log in you supply your username again and demonstrate with the password that you are the same person.

Edits you make are recorded under your username. If you are not logged in your edits are recorded under your IP address.

Logging in and setting preferences are currently done separately on each wiki. However, see Single signon transition.

Why log in?
You don't have to log in to read any MediaWiki wiki. You don't even have to log in to edit a MediaWiki wiki – anyone can edit almost any page, even without logging in.

However, it's still a good idea to log in, for these reasons:

 * Other users will be able to recognise you by your username when you make changes to pages. As a "name" an IP address is somewhat clumsy. Also, if you use computers at different locations (home, office, internet cafe, etc.) you have a different IP-address in each case; even in the same location, depending on the Internet connection, the IP-address may be different each time. Therefore a username is better to maintain an identity.
 * You will have your own user page where you can write a bit about yourself, and a user talk page which you can use to communicate with other users.
 * You will be able to mark an edit as minor, which avoids inconvenience for other users.
 * You will be able to keep track of changes to modules you are interested in using a watch list.
 * If you choose to give an email address, other users will be able to contact you by email. This feature is anonymous – the user who emails you will not know your email address.  You don't have to give your email address if you don't want to.
 * Check the privacy policy of the individual site you're visiting, if any (for example, Wikipedia's draft privacy policy)
 * You will be able to rename pages.
 * You will be able to set your own preferences, to change things such as:
 * The number of pages displayed in Recent changes
 * The fonts, colours and layout of the site, by using different skins.

How to log in
Logging in and setting preferences are done separately on each wiki (for plans of changing this see Single login). You may find it convenient for yourself and useful for maintaining a cross-wiki identity to use the same username on each wiki that you use, if that name is still free.

First, make sure that your browser accepts cookies. Some browsers can accept or reject cookies from individual sites; users of these should configure the browser to accept cookies from each wiki you plan to edit, such as wikipedia.org.

Go to the wiki for which you want to log in. Click on the Log in link at the top right of the page. You will then be prompted to enter your username and password. If you haven't logged in before, you will need to enter your password twice.

You may give your email address if you like. Other users will be able to send email to the address, but they won't be able to find out what the address is.

If you click the box Remember my password across sessions, you will not have to give your password again when you access MediaWiki wiki from the same computer. This feature will only work if your password was not generated by the Mediawiki software. So change your password please.

Log in problems
If you appear to be able to log in, but as soon as you try to look at a page after the 'Log in successful' page you appear logged out again, it is very likely to be a cookie problem. If you are certain that cookies are enabled, make sure that you haven't inadvertently listed the domain name of the wiki you are using (example: Wikipedia.org) on a list of sites to never allow cookies for (This feature is available in – at least – Mozilla Firebird 0.6 and above and Microsoft Internet Explorer version 6 and above). Also make sure your computer's date and time are set correctly; if they are not, cookies may expire before they are supposed to. In addition to these steps, check to make sure PHP's directory for storing session data is writable. This directory can be found in the php.ini file under the session.save_path setting.

If you log in and enabled the cookie feature, a subsequent log in as a different user without the cookie feature enabled will appear as logged out.

How to set preferences
Click on the Preferences link at the top right of the page for various options, including:
 * Changing your password.
 * Changing the skin, which changes the way that the web pages look.

See MediaWiki User's Guide: Setting preferences.

Your User page and User talk page
As a logged in user, you will be able to create your own user page and user talk page. When you are logged in, you will see your username displayed at the top right of the page. Click on this to get to your user page, which you can edit in the same way as any MediaWiki wiki page.

Most users write a little bit about themselves and their interests on their user page.

You also have a User talk page. You can access this by clicking on the Talk link next to your username at the top right of the page. Other people may write messages in your user talk page by editing it, and you can respond. See MediaWiki User's Guide: Talk pages for more..

How to log out
You can log out any time by clicking on the Log out link at the top right of the page.

How to force logging in for editing
This is controlled through a wg variable.

See Configuring access restrictions to your wiki.

how to force logging in for viewing
This is controlled through a wg variable.

See Configuring access restrictions to your wiki.

ja zh

title: Help:Logging in


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Help:Namespace

A namespace is a type of page in a wiki project. Page names with prefixes are probably associated with a category. Each wiki using the MediaWiki software has 16+2 namespaces: the main namespace, where page names have no prefix, 15 auxiliary types, each with its own prefix, and two pseudo-namespaces.

In each project they are similar to the 18 explained in w:Wikipedia:Namespace for Wikipedia. One of these is the project namespace, which uses as prefix the project prefix (variable     below).

Namespace uses

 * allows separation of different kinds of unrelated content;
 * several namespaces have special features related to their intended purpose
 * allows unrelated content to be stored in one wiki, but requires lots of extra typing
 * provides facilities to limit searches to a particular area
 * in principal allows easy exporting (but not with the Export feature, which is for selected individual pages) of a selection of work (categories could also be used for this more cleanly)
 * allows for feature separation

Namespace issues and ideas for improvements
Lots of programming languages have namespaces for their variables. Namespaces are commonly contained within curly braces "{}" and if a variable is referenced that is not included in the namespace, it might use the global namespace's variable.

Extensive content within a namespace causes lots of page name in place of page name typing, which isn't in the spirit of wikis. Nevertheless, it could be useful if the default would be to have the current namespace be searched first, and then the main namespace, or any other order of namespaces consulted.

Namespaces are used for a variety of features, including: interwiki linking, templates, and system messages. How are interwiki and namespace overlap issues dealt with?

Namespace benefits
(can namespaces go into their own tables, allowing for separation across servers?)

List of namespaces
The two pseudo-namespaces, main namespace and 15 auxiliary namespaces in this project (Meta) are the following (also the variables for them are shown):

Note that all characters of namespace prefixes are case-insensitive, so one can write e.g "mediawiki".

The names are set in files such as those listed in Locales for the Wikimedia projects, with default Language.php:

/* private */ $wgNamespaceNamesEn = array(	NS_MEDIA           => 'Media',	NS_SPECIAL          => 'Special',	NS_MAIN	            => '',	NS_TALK	            => 'Talk',	NS_USER             => 'User',	NS_USER_TALK        => 'User_talk',	NS_WIKIPEDIA        => $wgMetaNamespace,	NS_WIKIPEDIA_TALK   => $wgMetaNamespace . '_talk',	NS_IMAGE            => 'Image',	NS_IMAGE_TALK       => 'Image_talk',	NS_MEDIAWIKI        => 'MediaWiki',	NS_MEDIAWIKI_TALK   => 'MediaWiki_talk',	NS_TEMPLATE         => 'Template',	NS_TEMPLATE_TALK    => 'Template_talk',	NS_HELP             => 'Help',	NS_HELP_TALK        => 'Help_talk',	NS_CATEGORY	    => 'Category',	NS_CATEGORY_TALK    => 'Category_talk' );

Automatic conversions of page names
On the left in the table at the beginning of the previous section, a list of project-independent namespace names is shown, the same as those on Meta and the English Wikipedia, except that "Meta" and "Wikipedia" are replaced by "Project". The prefixes are the terms listed, followed by a colon.

The prefix "Project:" is for every project automatically converted to the project namespace, e.g. try the link Project:xyz. It is like a piped link. Therefore a page name starting with "Project:" is not possible (unless, of course, that is the name of the project).

Similarly the other project-independent namespace prefixes are also automatically converted to the project-specific ones.

Prefixes in various languages
For Wikimedia projects this project prefix is "Wikipedia:", "Wiktionary:", "Wikibooks:", "Wikisource:", "Wikiquote:", "Meta:", and in the case of In Memoriam also "Wikipedia:" (in French "Wikipédia:", in Czech "Wikipedie:", in Russian "Википедия:", in Korean "위키백과:", in Hindi "विकिपीडिया:", in Hebrew ":ויקיפדיה" and in Arabic ":ويكيبيديا"). The last two are RTL languages which put the prefixes on the right. In URLs the prefixes are always on the left.

To check which prefix is used, see e.g. the link "Contact us" or "Bug reports". "Talk", "User", "Image" and combinations can also be translated in the case of non-English wikis. see Locales for the Wikipedia Software.

Lists of pages
Oddly, for ordinary users there is no way to list all pages in the project, template, help and custom namespaces. A workaround would be to avoid these and use the main or another namespace, possibly using a non-system prefix, e.g. h:namespace instead of help:namespace.

See e.g.

Sysops can apply Special:Asksql when not disabled and use "SELECT cur_title FROM cur WHERE cur_namespace=10", etc. When disabled a form invites to submit a query, but then this leads to a HTTP 500 error.

Colon in page name
Adding a colon to a page name does not automatically create a new namespace. To see the namespace of a page, use which returns the namespace. For this page it returns "". The same code would return an empty string for a page in the main namespace. Similarly, returns the page name without prefix. For this page it returns "".

To take some examples from Wiktionary: Wiktionary:FAQ has Talk page Wiktionary talk:FAQ, but Wiktionary Appendix:Colours has Talk page Talk:Wiktionary Appendix:Colours, because the first is in the project preface namespace and the second is not. Accordingly the first is not in Special:Allpages but the second is. Unclear is why Wiktionary:Recentchanges is an exception.

Sites outside Wikimedia
Sites using MediaWiki but outside Wikimedia usually have their own project name as project prefix, but several have simply retained "Wikipedia:".

Interwiki linking is done with a prefix, that is similar to namespaces.

Special namespace
Main article: Help:Special pages

The namespace "Special:" consists of "special pages", which are created by the software on demand, for example Special:Recentchanges.

Custom namespaces
A project can have additional namespaces. For example, if a single project is multilingual (as opposed to the case of sister projects, each in one language) there may be a namespace Help: and also a namespace Hilfe:, for help pages in the English and German language, respectively.

For a full list of all namespaces for your project, see the search options of the preferences (Special:Preferences).

The list of custom namespaces is $wgExtraNamespaces in LocalSettings.php. Custom namespaces are numbered from 100. See also Help:Custom namespaces.

Tab labels
The first tab shows the namespace. See the link, if it is there, to see what it is in this project. For Meta-Wikipedia it is as shown on the right.

 * category: mediawiki:nstab-category => ""
 * help: 'nstab-help' => "Help",
 * main: 'nstab-main' => "content page",
 * file: 'nstab-file' => "File",
 * mediawiki: 'nstab-mediawiki' => "Message",
 * project: 'nstab-wp' => "About",
 * special: 'nstab-special' => "Special" - the tab is in an HTML element A without class or id, like an internal link, but it is not a link; to see the distinction, use a style for a:link and a:visited that is different from the style of just "a"
 * template: 'nstab-template' => "Template",
 * user: 'nstab-user' => "User page",

The second tab, linking to the talk page:

 * Talk: 'talk' => "Discussion"

On a diff page or a page with an old version, the links are to the current version (however, the edit tab on a page with an old version links to the edit page of that old version; this does not apply on a diff page comparing two old versions, there the edit tab links to the edit page for the current version).

The self link feature (a self link appearing as bold text) does not work for the tabs, no distinction is shown between a self link and a link to a different (version of a) page.

With the class "selected" one can let the tab for the same namespace as the current page (either a self link or a link to the current revision) be displayed differently; also the tabs "edit" and "history" are then displayed in this different way when applicable.

title: Help:Namespace


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Help:Navigable images

In projects that allow embedding images in external link style, an image can be used as "link label":

Compare, also an internal image, linking to the same internal page. Note that on the target page a redirect message is shown, while also the image is inserted in that page. This method is possible on all projects.

title: Help:Navigable images


text:
Help:Formula

TeX
MediaWiki uses TeX markup for mathematical formulae. It generates either PNG images or simple HTML markup, depending on user preferences and the complexity of the expression. In the future, as more browsers are smarter, it will be able to generate enhanced HTML or even MathML in many cases.

Math markup goes inside  $$ ... $$ . The edit toolbar has a button for this.

The PNG images are black on white (not transparent). These colors, as well as font sizes and types, are independent of browser settings or css. Font sizes and types will often deviate from what HTML renders. The css selector of the images is img.tex.

In the case of a non-white page background, the white background of the formula effectively highlights it, which can be an advantage or a disadvantage.

One may want to avoid using TeX markup as part of a line of regular text, as the formulae don't align properly and the font size, as said, usually does not match.

The alt attribute of the TeX images (the text that shows up in the hover box) is the wikitext that produced them, excluding the $$ and $$.

Discussion, bug reports and feature requests should go to the Wikitech-l mailing list. These can also be filed on MediaZilla under MediaWiki extensions.

General
Spaces and newlines are ignored. Apart from function and operator names, as is customary in mathematics for variables, letters are in italics; digits are not. For other text, to avoid being rendered in italics like variables, use :   gives $$\mbox{abc}$$

Line breaks help keep the wikitext clear, for instance, a line break after each term or matrix row.

Functions, symbols, special characters
For producing special characters without math tags, see Help:Special characters.

Comparison:
 * &alpha; gives α, $$\alpha$$ gives $$\alpha$$ ("&" and ";" vs. "\", in this case the same code word "alpha"
 * &radic;2 gives √2, $$\sqrt{2}$$ gives $$\sqrt{2}$$ (the same difference as above, but also another code word, "radic" vs. "sqrt"; in TeX braces)
 * &radic;(1-e&sup2;) gives √(1-e²), $$\sqrt{1-e^2}$$ gives $$\sqrt{1-e^2}$$ (parentheses vs. braces, " e " vs. "e", "&sup2;" vs. "^2")

Parenthesizing big expressions, brackets, bars
You can use various delimiters with \left and \right:

Spacing
Note that TeX handles most spacing automatically, but you may sometimes want manual control.

Align with normal text flow
Due to the default css

img.tex { vertical-align: middle; }

an inline expression like $$\int_{-N}^{N} e^x\, dx$$ should look good.

Forced PNG rendering
To force the formula to render as PNG, add \, (small space) at the end of the formula (where it is not rendered). This will force PNG if the user is in "HTML if simple" mode, but not for "HTML if possible" mode (math rendering settings in preferences).

You can also use \,\! (small space and negative space, which cancel out) anywhere inside the math tags. This does force PNG even in "HTML if possible" mode, unlike \,.

This could be useful to keep the rendering of formulae in a proof consistent, for example, or to fix formulae that render incorrectly in HTML (at one time, a^{2+2} rendered with an extra underscore), or to demonstrate how something is rendered when it would normally show up as HTML (as in the examples above).

For instance:

This has been tested with most of the formulae on this page, and seems to work perfectly.

You might want to include a comment in the HTML so people don't "correct" the formula by removing it:

Examples
$$\frac{2}{3-x} = \frac{3}{2-x}$$

$$\left(3-x\right) \times \left( \frac{2}{3-x} \right) = \left(3-x\right) \times \left( \frac{3}{2-x} \right)$$

$$2 = \left(3-x\right) \times \left( \frac{3}{2-x} \right)$$

$$2 = \left( \frac{\left(3-x\right) \times 3}{2-x} \right)$$

$$2 = \left( \frac{9-3x}{2-x} \right)$$

$$2 \times \left(2-x\right) = \left(2-x\right) \times \left( \frac{9-3x}{2-x} \right)$$

$$2 \times \left(2-x\right) = \frac{\left(2-x\right) \times \left(9-3x\right)}{2-x}$$

$$2 \times \left(2-x\right) = 9-3x \!$$

$$4-2x = 9-3x \!$$

$$-2x+3x = 9-4 \!$$

$$x = 5 \!$$

title: Help:Formula


text:
Help:Images and other uploaded files

To add an image, the image file has to be uploaded. Also other files can be uploaded, see below. The system uses the term "image" for any uploaded file.

First give the file a suitable name, because renaming during or after uploading is not possible. Make sure that the file name has the proper extension. With the file an image description page will be associated, with a page name consisting of the file name (including extension), prefixed with "File:" (or in general the value of variable     ). Thus the file names are case-sensitive (this applies even for the file name extension) except, in most projects, for the first character.

Although on each projects files can be uploaded, a family of projects may have designated one in particular for this, with sharing of those files enabled. For Wikimedia projects this is Wikicommons (free content only, no "fair use" content), in general this is referred to below as Commons.

To upload a file, go to Commons, log in there, and upload the file using the Upload link.

If you want to replace an existing file, give it the same name, and otherwise a name that does not exist yet. Be careful with replacing or deleting an image on Commons, a complication is that the "Image links" section on the image description page on Commons does not show usage of the image by other projects.

Apart from text, MediaWiki supports the following media inline:
 * images -- preferred formats: PNG, JPEG.

Currently SVG images can be uploaded and linked to, but not be embedded, e.g. (image description page) - see also SVG image support.

There may be a size limit, the largest one on en: is 3.5 megabytes (but please be reasonable).

The most common type of media apart from images is:

 * sound -- preferred format: Ogg Vorbis.

If you want to upload other file types then .jpg or .ogg (like for example .pdf) in newer versions of MediaWiki, you have to modify the file LocalSettings.php accordingly: $wgFileExtensions = array( 'png', 'jpg', 'jpeg', 'ogg','doc','xls','ppt','mp3','sxc','pdf' );

Remarks:

 * Wikimedia specific: see Video policy
 * for reasons of security executable programs are not allowed by default

Images can also be produced by the system from specifications in wikitext:
 * Formulas (e.g. )
 * Timelines, navigational maps, etc. (e.g. )
 * thumbnails of uploaded images (e.g. ]) (saves bandwidth compared with letting the browser do the reduction)

Linking
To link to the file use ":File:" instead of "File:", e.g. File:So.gif (the first colon is not displayed).

Piped links work as usual.

Interwiki link style gives a link to the image description page. For embedding (if possible, see below) and linking to the file itself, use external link style.

If interlanguage links would be applicable, use a colon in front of the language code, e,g. de:Bild:Europa-Pos.png, to avoid the link being put in the margin.

External link syntax is as usual. However, if you want a link to an image proper on a page of a project that allows embedded external images, use a bracketed link syntax and not just the URL, to prevent embedding.

Embedding internal images
"Internal" refers to both the same project and Commons. An image name is assumed to refer to the one in the same project if it exists there, otherwise to one on Commons.

Only images proper can be automatically presented, sound is not automatically played.

To add the uploaded image to an article, write something like

To embed an image, one can use, e.g.  which gives the image on the right. The caption can contain links.

This format allows both size reduction and enlargement. Both the image itself and an icon link to the image description page with the image in its actual size. The link title of the icon is "Enlarge", even in cases where this term does not apply, because it leads from the enlarged image to the one with the actual size.

For more possibilities, see Extended image syntax. Also, the source of existing pages with images are useful as examples.

Image at the left
  puts the image at the left; text that follows floats around it; a second image immediately after the first is put to the right of it, if there is text in between then the second image is at the lower right of the first, under this text:

text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text

With   the image is put at the left, and text that follows starts below it.

text text text text text text text text text text text text text text text text text text text text text text text text text text text text

Image at the right
  puts the image at the right; text that follows floats around it. The situation is not symmetric with the case above: a second image is put at the extreme right again.

text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text

Using full width again
Use   , or on projects that have Template:Clear (Meta and en:):

.

Inline images
Inline images cannot have a caption, but they can have an "alt"-attribute, e.g. shown in the hoverbox (in the cases above, for the image it is the same as the caption, and for the enlarge icon it is "Enlarge"). It is the last item of the image code, hence, if there is only the image name with prefix "File:" it gives that; if there is an empty item by ending with a pipe character it gives the name without prefix; otherwise, it gives the image code item that happens to be last, unless a proper text is specified.

The size of the images can be reduced but they can not be enlarged.

text text  text  text

gives: text text  text  text (also note the hoverbox).

See also below.

Embedding external images
External images can not always be embedded, this depends on the settings of the project: it has been disabled on many of the larger Wikipedias, including the English and German, to prevent vandalism and bandwidth theft from other sites, but it is allowed on many other Wikimedia projects, including Meta and the Dutch Wikipedia.

If enabled on this project there is an image here, otherwise just a link to an image: http://en.wikipedia.org/upload/b/bc/Wiki.png

Currently the following public MediaWiki wikis do not allow external images:
 * English Wikipedia

If necessary, download an image of a project and upload a copy into the Commons project, you can then use it on all projects.

The examples in what follows are intended for projects in which embedding is enabled.

If enabled, use unbracketed external link style, i.e. just the URL (of the image itself, not of the image description page), e.g. http:// en.wikipedia.org/upload/d/d1/Tile_Hill_train_550.jpg. The URL can be found by checking with your browser the properties of the image when it is displayed on a webpage.

Conversely, to go to the image description page of an image referred to with external link style, put the URL in the address bar and replace "upload/number/number/ " with "wiki/File:".

For inline images, put the URL, followed by a space, in the text: a http:// meta.wikimedia.org/upload/2/27/Tst.png b gives ahttp://meta.wikimedia.org/upload/2/27/Tst.png b

Without special formatting, inline images are positioned like this:

text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text http://en.wikipedia.org/upload/b/bc/Wiki.png text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text

A table may be used to position the image(s) as desired. E.g.

gives

Similarly

Navigational maps
Navigational maps like  have map areas linked to pages. The HTML with tags can not be put in the wikitext. However, EasyTimeline allows the creation of an image and a page embedding that image, with tags for rectangular map areas in the HTML. The title of a link to a non-internal page is only the domain name, e.g. "en.wikipedia.org/..". The length and width of the rectangle can not be controlled, except that it depends on the length of the link lable and its font size. In case of overlap of rectangles one has to look at the hoverbox or statusbar to avoid following the wrong link. In case of much overlap it may not be possible to use all links.

Examples:

Some attempts for other alternatives (note the hover boxes):

Ascii art map, with both the city outline and the label clickable:

x xxx Leiden x

xx xxxx The Hague xxx

xx xxxxx Rotterdam xxxx

When external images can be embedded:

The HTML titles are "w: Leiden", etc., the alt attribute is "Tst.png". Opera shows the title in the hoverbox, and also the URL, IE only shows the alt.

With labels:

See also Maps, Maps' clickability.

Uploading
On most browsers, you will see a "Browse..." button, which will bring up your operating system's standard file open dialog. Choosing a file will fill the name of that file into the text field next to the button. You must also check the box affirming that you are not violating any copyrights by uploading the file. Press the "Upload" button to finish the upload. This may take some time if you have a slow internet connection.

The preferred formats are JPEG for photographic images, PNG for drawings and other iconic images, and OGG for sounds. Please name your files descriptively to avoid confusion.

Please note that as with wiki pages, others may edit or delete your uploads if they think it serves the project, and you may be blocked from uploading if you abuse the system.

When a file is uploaded with the same name as an existing one, the old one is replaced. If that is not the intention one has to check in advance that the same name does not exist yet, because currently the system does not warn against overwriting. For example, click on http://meta.wikipedia.org/wiki/File:A and replace the A in the address bar of the browser with the file name. Alternatively use the search feature in Special:Imagelist.

When a media file is replaced by uploading a new one with the same name (e.g. an image in an article is replaced), this does not show up in the page history of the article, nor in the Related Changes of the article, nor in the revision history of the image description page (unless the description section is also changed). However, it is recorded in the Image History section of the image description page, and it changes Upload log. Therefore, to watch changes in images in an article, it is not sufficient to watch the article itself and the image description pages ("watching" in the sense of putting on the list of "watched pages"), but one should watch the Upload log also.

Special:Imagelist provides the same information as the Upload log, but it uses the user's local time instead of the default time (set to UTC for Wikimedia projects). In addition it gives the file sizes. Further it allows loading of portions and sorting by size in addition to sorting by date, and it has not only links to the image description pages, but also directly to the images.

 * Last 50 uploaded files
 * MediaWiki file usage - technical notes

Uploading non-image files
By default, MediaWiki only allows you to upload certain types of files (extensions gif, jpg, jpeg, ogg and png). This is managed by this order in includes/DefaultSettings.php:
 * $wgFileExtensions = array( 'png', 'gif', 'jpg', 'jpeg', 'ogg' );

If you want to be able to upload other file typs, for instance ZIP files you must add this line to LocalSettings.php:
 * $wgFileExtensions = array( 'png', 'gif', 'jpg', 'jpeg', 'ogg', 'zip');

Caution: do not modify the line in DefaultSettings.php because it will break when updating

Take in account there is a blacklist of file extensions in includes/DefaultSettings.php:

 * $wgFileBlacklist = array(
 * # HTML may contain cookie-stealing JavaScript and web bugs
 * 'html', 'htm',
 * # PHP scripts may execute arbitrary code on the server
 * 'php', 'phtml', 'php3', 'php4', 'phps',
 * # Other types that may be interpreted by some servers
 * 'shtml', 'jhtml', 'pl', 'py',
 * # May contain harmful executables for Windows victims
 * 'exe', 'scr', 'dll', 'msi', 'vbs', 'bat', 'com', 'pif', 'cmd', 'vxd', 'cpl' );

More details and examples on embedding internal images into articles
To include the image in a page, use a link in the form or or  for sounds.

Example: Using, the image Canterbury Tales.png is included:

If the wiki is set to another language than English, the name of the "File:" namespace might be changed. For German, for example, it's Bild:Canterbury Tales.png

Alternate Text
By specifying alternate text, you can make the article accessible to the blind, too. You can specify an alternate text after a "|"-sign, e.g., which will look like this:

Layout and resizing
Several options can be set when including an image. Those affect the placing of the image, its size or the way the image will be presented. Those options are specified between the image name and the alternate text:. Available options are:

 * thumbnail, thumb : generates an automatically resized thumbnail image, normally on the right, with the caption text displayed directly underneath. An "enlarge"-icon is added. Example:  Canterbury Tales.png
 * right : make the image right-aligned, can be used with and without specifying thumb
 * left : same as above, but left aligned.
 * frame : The image will have a frame, regardless of whether it is a thumb, and the caption text will be included as a visible caption.
 * sizepx</tt> : render a thumbnail version of the image that's [size] pixels wide (e.g. '150px'). Height is computed to keep aspect ratio (i.e. the shape of the image).

Vertical bars are used to separate options from each other and from the caption text. Unknown options are skipped and the last option is used as the caption text.

The options can be combined, e.g. as (shown on the left).

Demo
Below one can see the result of the three types of internal link style and external link style on this project. To test this in another project, copy the wikitext there. If applicable, check also the interlanguage links at the margin of the page. Note that some links go to the image description page, others just to the image itself.

 * w:File:Tile Hill train 550.jpg

w:File:Tile Hill train 550.jpg
 * w:File:Tile Hill train 550.jpg

 * en:File:Tile Hill train 550.jpg

train
 * external, with label: train

 * external, footnote style:

 * external, just the URL: http://en.wikipedia.org/upload/d/d1/Tile_Hill_train_550.jpg http://en.wikipedia.org/upload/d/d1/Tile_Hill_train_550.jpg

Revision history of pages containing images
Pages in the stored Help:page history consist of wikitext with possible references to templates and images. When viewing an old version of a page, these refer to the current versions of the templates and images, if these still exist. Thus the former composite page is not reconstructed.

Default settings
 This is the list of preferred extensions for uploading files. Uploading $wgFileExtensions = array( 'png', 'jpg', 'jpeg', 'ogg' );
 * 1) files with extensions not in this list will trigger a warning.

$wgFileBlacklist = array(	# HTML may contain cookie-stealing JavaScript and web bugs	'html', 'htm',	# PHP scripts may execute arbitrary code on the server	'php', 'phtml', 'php3', 'php4', 'phps',	# Other types that may be interpreted by some servers	'shtml', 'jhtml', 'pl', 'py',	# May contain harmful executables for Windows victims	'exe', 'scr', 'dll', 'msi', 'vbs', 'bat', 'com', 'pif', 'cmd', 'vxd', 'cpl' );
 * 1) Files with these extensions will never be allowed as uploads.

$wgCheckFileExtensions = true;
 * 1) This is a flag to determine whether or not to check file extensions on
 * 2) upload.

$wgStrictFileExtensions = true;
 * 1) If this is turned off, users may override the warning for files not
 * 2) covered by $wgFileExtensions.

$wgUploadSizeWarning = 150000;
 * 1) Warn if uploaded files are larger than this

Linking to an enlarged image
Unfortunately, when linking to an image, no parameters can be specified except the link label, e.g. ). Also, when linking to a template instead of embedding it, transfer of parameters is not possible.

Thus one cannot link to an enlarged image unless one has prepared a page containing that enlarged image, e.g. help:tst.png (large). The large image has been put here in the Help namespace, alternatively it could have been in;
 * the image description page (in that case some scrolling is required to see the image history and the pages using the image, but this can be made more convenient with a TOC)
 * its talk page (ditto, to see the talk)
 * a separate page in the image name space, like File:Tst.png (large).

Also, when linking to a template instead of embedding it, transfer of parameters is not possible. This would have been useful e.g. to link to an enlarged image.

title: Help:Images and other uploaded files


text:
Help:ISBN links

For a book with ISBN e.g. 0131103628, Special:Booksources/0131103628 gives the text of MediaWiki:Booksourcetext and links regarding the book according to the value of $wgBookstoreListEn in Language.php, currently: /* private */ $wgBookstoreListEn = array(	"AddALL" => "http://www.addall.com/New/Partner.cgi?query=$1&type=ISBN",	"PriceSCAN" => "http://www.pricescan.com/books/bookDetail.asp?isbn=$1",	"Barnes & Noble" => "http://shop.barnesandnoble.com/bookSearch/isbnInquiry.asp?isbn=$1",	"Amazon.com" => "http://www.amazon.com/exec/obidos/ISBN=$1" );

Alternative
No template is required for providing links for ISBNs.

Instead simply type ISBN before the number with no spaces or colons. Hyphens are not required, but are preferred if their proper placement is known.
 *  ISBN 1413304540   produces ISBN 1413304540
 *  ISBN 1-4133-0454-0   produces ISBN 1-4133-0454-0
 *  ISBN 9781413304541   produces ISBN 9781413304541
 *  ISBN 978-1413304541   produces ISBN 978-1413304541
 *  ISBN 978-1-4133-0454-1   produces ISBN 978-1-4133-0454-1

title: Help:ISBN links