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Wikijunior:Solar System/Jupiter/Io

Io Facts:
 * Io is the most volcanically active body in the Solar System.
 * Io is one of the few moons to have an atmosphere although it is very thin.
 * At any given time, there are approximately 9 volcanoes erupting on Io.
 * Io is so close to Jupiter that Jupiter causes "tides" in its surface. These "tides" are what makes it so volcanically active.
 * Io is one of only five of Jupiter's moons that can eclipse the Sun as seen from Jupiter.
 * Io is the fourth-largest moon in the solar system.

Io is the innermost moon to Jupiter. Be careful not to confuse Io the moon with 85 Io, an asteroid, or with I.O., an abbreviation that can stand for a number of different things.

How big is Io?
Jupiter has 66 moons, but only four are large ones comparable to our Moon. Io is one of these four, and the third largest. Io is 3642.6 km, or 0.28 Earths, wide. It only has a mass of about 1.4% of the mass of Earth. It is a similar size to our Moon (but a lot more exciting!).

What is its surface like?

Unlike most moons, Io has a "young" surface. Because there is so much volcanic activity, the surface is almost free of craters. Also, its volcanoes are quite unusual. Because of the low gravity of Io and the explosiveness of the volcanoes, sometimes they eject material as far as 500 km above the ground. 500 km is more than the distance from ground level on Earth to the International Space Station. Sometimes the volcanoes erupt more calmly, more like geysers on Earth. There are also shield volcanoes on Io, formed mostly from lava flows.

The temperature of Io varies wildly. At some spots, near volcanic eruptions, the temperature is very hot. But most of Io is very cold, as it is so far away from the sun. The average temperature of Io is -143°C. This is much colder than −90°C, the coldest it gets in Antarctica.

In addition to volcanoes, Io also has many mountains, lakes of molten sulfur, calderas, and flows of molten sulfur or silicate hundreds of kilometers long. The colour of the surface is due to sulfur being at different temperatures. When sulfur warms up and cools down, it changes colour. This is why the surface of Io has so many colours. Some people think it looks like a pizza!

Io has 10 named regions (regions on the Earth would be the Middle East, the Far East, the West, etc) which all end in the word Regio, which means in Latin Region. All of the regions are named after ancient kingdoms and empires of Earth, similarly to how most planets and stars are named after gods and other characters from mythology. For example, the largest regio, Colchis Regio correlates to Colchis Kingdom in 550-164 BC.

Io's volcanic features are all based on various beings in mythologies other than Greek mythology and Roman mythology. For example, Masubi is a volcano, but in Japanese mythology, he is the deity of fire who is said to have caused 8 volcanoes on earth. Another example would be another volcano named Ra. Ra in Egyptian mythology was the god of the sun.

Io's mountains are a mix of many mythologies, in the aspects of their names. They all end in several Latin words vaguely meaning mountain. Danube Planum is based on the Danube river, which runs from southwest Germany to the Black Sea, while Egypt Mons is based on Egypt. On the other hand, there are mountains such as Epaphus Mensa, named after Epaphus, son of Io and Zeus; and Ot Mons — in Mongolian mythology, Ot Ene (the final "e" is pronounced) is the goddess of marriage, who was born at the beginning of the world, when the sky and the earth separated.

How long is a day on Io?

It takes 42 hours (1¾ Earth days) for Io to rotate on its axis. It also takes 42 hours for Io to complete one orbit around Jupiter. Since these numbers are the same, it means that the same side of Io always faces Jupiter. (Earth's moon is the same way, which is why you can always see the Man in the Moon.)

Who is it named after?
Io (Ancient Greek Ἰώ) — pronounced eye-oh — is named after one of Zeus' (Jupiter's) 1000 lovers. She was a nymph. Nymphs are spirits of nature, associated with water, forests, and grottoes. According to the legend, Io was transformed into a cow by Zeus in order to hide her.

How would Io's gravity pull on me?
If you stood on the surface of Io, you would weigh less than you do on Earth. A person who weighs 200 pounds (90kg) on Earth would weigh about 36 pounds (16kg) on Io. So the gravity, of course, pulls less on you.

How was it discovered?

Io was discovered by both Simon Marius and Galileo Galilei. Galileo discovered it on January 7, 1610, and Marius discovered it around the same time.

Wikijunior Sonnensystem/ Jupiter/ Io Wikijunior Il sistema solare/Giove/Io

title: Wikijunior:Solar System/Jupiter/Io


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Wikijunior:Solar System/Jupiter/Ganymede

Ganymede Facts:
 * Ganymede is the only moon of Jupiter discovered by Galileo to be named after a male person.
 * Ganymede, the Solar System's largest moon, is larger than either Mercury or Pluto.
 * Ganymede is the only moon to have a magnetic field.
 * Ganymede is the largest moon in the solar system.

How big is Ganymede?
Ganymede is 5262.4 km, or 0.413 Earths wide, making it a little larger than the Earth's moon. It is the largest of Jupiter's moons — in fact it is the largest moon in the solar system.

What is its surface like?
The surface of Ganymede is divided into two regions: dark regions, and light regions. The dark regions are very old and highly cratered, while the light regions are younger (but still quite old), and marked by grooves and ridges. However, craters are found on both types of terrain, and are around 3 to 3 1/2 billion years old.

Ganymede's crust is made of water ice. Like Earth's crust, it is broken up into plates, which can move. Along the fracture zones, mountain ranges have formed. Because the crust can flow, craters tend to be flat. Sometimes, old craters become palimpsests because of erosion casued by the crust.

Recently, the Hubble Space Telescope found evidence of an oxygen atmosphere on Ganymede. This does not mean that there is life on Ganymede; it is believed that the oxygen is produced when radiation splits the water ice (H2O) into hydrogen and oxygen. The hydrogen is lost because it has a low mass, while the oxygen forms the atmosphere.

How long is a day on Ganymede?
One day on Ganymede is equal to about 7.15 days on Earth.

How long is its orbit around Jupiter?
It takes Ganymede 7.15 days to orbit Jupiter. Ganymede orbits Jupiter at the same speed that it spins.

Who is it named after?
Ganymede (Greek Γανυμήδης) is named after a handsome Trojan boy who was made cupbearer to the gods by Jupiter (also known as Zeus).

How was it discovered?
Ganymede was discovered by Galileo Galilei and Simon Marius. Galileo found it on January 11, 1610, and Marius around the same time.

Wikijunior Sonnensystem/ Jupiter/ Ganymed

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


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Wikijunior:Solar System/Jupiter/Callisto

How big is Callisto?
It is Jupiter's second largest moon, after Ganymede, and the third largest moon in the solar system. It is a little more than one third the size of the earth.

What is its surface like?
The surface of Callisto is one of the most cratered in the Solar System. In fact, impact craters are the only features found on the surface. Because Callisto's surface is icy, large craters and mountains are slowly erased. Callisto's crust is about 4 billion years old, dating back to the formation of the Solar System.

The largest crater on the surface is Valhalla. It measures 3000 km across. The second largest crater, Asgard, measures 1600 km across. Gipul Catena, a series of craters in a straight line, was probably caused by an object that was tidally disrupted as it passed close to Jupiter.

There is no oxygen in the atmosphere. Under the rocky crust of the surface there is a salty underground sea.

How long is a day on Callisto?
One day on Callisto is equal to approximately 16.7 days on Earth. Callisto Facts:
 * Callisto's crust dates back to the formation of the Solar System.
 * A salty ocean may lay beneath the crust.
 * It is the second largest of Jupiter's moons.

How long is its orbit around Jupiter?
One orbit around Jupiter is also equal to 16.7 days on Earth.

Who is it named after?
Callisto (Greek Καλλιστώ) is named after the Greek Mythological nymph named Kallisto, which meant "most beautiful" in Greek. Kallisto was one of Zeus' many lovers.

How was it discovered?
Callisto was discovered by Galileo Galilei and Simon Marius. Galileo discovered it on January 7, 1610, and Marius observed it around the same time.

Wikijunior Sonnensystem/ Jupiter/ Kallisto


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Wikijunior:Solar System/Jupiter/Amalthea

Amalthea Facts: Amalthea is the third moon of Jupiter. Amalthea's oribt is very close to the Amalthea gossamer ring.
 * Amalthea is the reddest object in the Solar System, even redder than Mars.
 * Before 1975, Amalthea was not considered the official name (though it had extensive informal use) of the moon. Prior to the current name, it was called Jupiter V.

How big is Amalthea?
Amalthea is not spherical like a ball, instead it looks like an asteroid. In fact, there is an asteroid in the asteroid belt named 113 Amalthea. However, the asteroid is completely unrelated to the moon. This moon of Jupiter has an average diameter of 172 km. The entire moon is actually a bit smaller than Ireland.

What is its surface like?
The surface of Amalthea is bright crimson. The reddish colour may be from sulfur or some other non-ice material. Amalthea has multiple craters, but only two are named: Pan, named after the Greek god of the wild; and Gaia, goddess of the Earth. Amalthea also has two named mountains, both named after places in Crete, the largest island of Greece: Lyctos Facula, named after Lyctos; and Ida Facula, named after Mount Ida. Facula, in Latin, means a small torch.

How long is a day on Amalthea?
One day on Amalthea is equal to about half of an Earth day. One day is 11 hours, 57 minutes, and 23 seconds, barely more time than Jupiter takes to rotate.

How long is its orbit around Jupiter?
One orbit around Jupiter also takes the same time as a day on Amalthea — about half of an Earth day. Since these two times are the same, the same side of Amalthea always faces Jupiter. Earth's moon is the same way, which is why you can always see the Man in the Moon.

How would Amalthea's gravity pull on me?
If you stood on the surface of Amalthea, you would weigh only 1/555 of what you do on Earth. A one hundred pound person would weigh only 0.18 pounds on Amalthea, which is a little more than ten 50p, or 14 quarters! This means that if you could lift ten kilograms on earth, you could hold three cars on Amalthea. The strongest weightlifter would be able to lift a blue whale, the heaviest animal on Earth.

Who is it named after?
Amalthea (Greek Ἀμάλθεια) is named after a nymph in Greek myths who nursed Zeus, which is the Greek counterpart of the god Jupiter, with goat's milk.

How was it discovered?
Amalthea was discovered on September 22, 1892 by Edward Emerson Barnard, using the 36 inch (91 cm) refractor telescope at Lick Observatory, in California. He was the first to discover a new moon of Jupiter since Galileo discovered Io and Europa in 1610.

Wikijunior Sonnensystem/ Jupiter/ Amalthea Wikijunior Il sistema solare/Giove/Amaltea


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User:Rachel Knott

 * Im Theresa Knott's daughter.

title: User:Rachel Knott


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Raising Chickens/Feeding

Feeding chickens is almost as easy as watering them. In nature chickens are the garbage cleaners of the south east Asian jungle. For everyday food you can feed your chickens either chicken food (found at feed stores) or pig food. In Alberta the UFA Hog Grower is the same as the chick starter except the pellets are bigger, and the hog grower contains less antibiotics. If you have access to grain then you can feed that to them. Whenever you make food with lots of scraps (peelings and bits of vegetables that humans shouldn't eat) then feed those to them. Chickens can be trained so well if they see a small bucket (for carrying chicken scraps) they get excited because a treat is coming. You can feed your chickens in a trough, appropriate sized container, or by scattering the food on the ground. You can even give your chickens bones with scraps of meat on them. There is very little that they won't eat.

Information Specific to Laying Hens
Laying hens require calcium for egg shells. During the laying season, put a pile or box of crushed clam shells in their pen. Crushed clam shells are available at most local feed/farm stores. If you scatter the clam shells too much, you won't know when the hens need more until you see paper-thin shells. Egg shells also work for the calcium, but you run the risk of the birds learning to eat their own eggs. To avoid this you should crush the shells so that they don't look like eggs.

Other Information
If you have any questions about whether chickens should eat a particular food or not post your question on the Raising Chickens/Feeding discussion page.

Lettuce, cauliflower and cabbage leaves Feel free to add items that you have found chickens shouldn't or won't eat though just like people they are individuals and all have their own likes and dislikes so it cannot be justly said that they WILL or WILL NOT eat a certain food.

Cheese: My chickens go mad for cheese. It is very fatty however and should not be given in abundance.

And finally, NEVER, NEVER, NEVER feed chickens (or any other bird) avocado. Avocados (their peelings, the fruit itself, and the seeds) are POISONOUS TO BIRDS.

title: Raising Chickens/Feeding


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Talk:Raising Chickens/Feeding

My chickens love this!
Post food that your chickens love here Klingoncowboy4 22:35, 2 Jul 2005 (UTC)

Laying hens require calcium for egg shells. During the laying season, put a pile or box of crushed clam shells in their pen. Crushed clam shells are available at most local feed/farm stores. If you scatter the clam shells too much, you won't know when the hens need more until you see paper-thin shells. Egg shells also work for the calcium, but you run the risk of the birds learning to eat their own eggs.

The only time I pen/cage my birds is when they hatch a clutch of chicks. (Normally, they and all the other critters on the farm run around together.) When they're penned or caged the thing they love most is greens. I usually throw in bunches of grasses and garden weeds. You might be able to get someone that doesn't spray their lawn to let you rake their clippings for your birds.

I am new to chicken raising - having inherited 6 chickens from the previous owner of the house. At present i am only giving them 'Crumble' and fresh water, but from reading here it sounds like they need more! if I give them 'greens' do i need to chop them up i.e. cabbage, green beans etc? Wha about califlower stalks? Potatoe skins? Any advice would be appreciated! (lfnolan@attglobal.net)

We pull up full cabbage from the neighbouring fields and give them to our chickens and they love them. They will peck at and tear off chunks of leaf and peck at the roots and soil on the roots. They struggle with the solid heart and the stalk though. They will eat cabbage and greens cooked as well. As a general rule of thumb, if its hard and solid they can't cope with it very well, try cooking it and mashing or chopping it. If its reasonably soft or leafy they will shred it themselves. They are not stupid and they know what they like. If they don't eat what you give them stop giving them it. If something makes them feel ill they quickly learn to stop eating it. (so long as it isn't so poisonous it kills them outright, but I've not come across anything like that yet.)We even have laburnum trees and the seeds go everywhere and are poisonous, they just know not to eat them. So don't worry too much about what you are giving them, they'll let you know if they don't like it.

Oatmeal, dry or prepared. Corn. Sunflower seeds (cracked open). Old Cereal. Bread. Grapes (pinch in half or they cant get a grip to peck on) Watermelon rinds.

Our chickens love baked beans, but won't eat carrots or sweet potato, so we think they possibly don't usually like orange things, as they won't eat orange peel either. They also eat leftover toast, but it helps if you soak it first, otherwise they tend to leave little bits and then you can end up getting rats. They will eat pretty much anything, but we gave them curried lentils the other day, and it made their eggs taste of curry, so we won't be doing that again!

Our chicken love cooked oatmeal. Warm too.

Can I feed my chickens this?
Post your questions about feeding chickens here. Klingoncowboy4 22:35, 2 Jul 2005 (UTC)

"Because they are chickens. Although chickens will happily eat chicken and other meat products. After butchuring a chicken you can leave the skeleton in the the pen and they will pick the bones clean. If done on a large scale, making chicken feed from chickens (especially the brain and spinal cord) can lead to an outbreak of encephalopathy, similar to mad cow disease."

This does bring up an interesting point. Chickens being scavangers will eat meat. Is it safe for chickens to eat a diet a meat products including but not limited to poultry? I havn't given my chickens much meat products other than what is in UFA Hog Growers. My dogs end up with most of the meat producsts that people don't eat. I have even started giving moldy buns to my dogs instead of chickens. The chickens don't seem to care too much about the buns anymore. My dogs love them, they are almost like Dog candy. BTW if you are intersted in Buns for Dogs what I ended up doing was given them some old Costco buns that had gone moldy. Klingoncowboy4 21:36, 4 December 2005 (UTC)

Chickens naturally eat meat. They love nothing more than a good juicy worm, in fact I virtually get mugged now when I get the spade out of the shed as they know it means digging and worms. So I don't think meat in their diet is a problem. Our chickens get left overs from all our family and neighbours and they are pretty happy and healthy on it. Do snails count as meat? Because they love them and the shell would probably supply calcium.

Chickens Can't/Won't eat this
Post foods that you have found that chickens can't or won't eat here Klingoncowboy4 22:35, 2 Jul 2005 (UTC)

Chocolate can be fatal for birds.

User:Hajhouse adds:

 * My chickens don't like rye kernels
 * Aledgedly chickens can't digest raw potatoes

They seem to love potatoes! Prefer cooked to raw, as well as prefering them mashed to whole; easier for them to eat.82.38.78.129 13:55, 25 April 2006 (UTC)

DO NOT feed chickens or people GREEN potato peels!!! Since potatoes are part of the nightshade family (like tomatoes, eggplant and deadly nightshade) if the peels get green from exposure to the sun they develop vastly increased levels of solanine which is toxic in very small quantities. Solanin is the same poison that is concentrated in deadly nightshade & tomato leaves. That's why you peel off the skin from greened potatoes, and it's better not to eat them at all! Icre8arch (talk) 22:53, 20 November 2010 (UTC)

The presentation of this information seems very muddled up, it starts up saying that Chickens shouldnt or cant eat something and gives a reason for it and yet in the same table shows things that they love to eat. This really needs ot be broken down into two separate tables with one only showing stuff they shouldnt eat with a justification against each item and the other showing stuff they do like to eat rather than including both in one table entitled stuff that shouldnt eat.

Gave them bananas and they didn't seem to care for them. I guess it was too mushy for them??

A lot of leafy greens like bok choi and lettuce they seem to ignore. Nothing the least bit spicy, salty or peppered. Tried giving them pill bugs as 'meat' along with snails. They rolled the pill bugs around and gave me the look. You want me to eat WHAT?

Bananas
According to the chart chickens don't like Bananas however, I have received a message saying I feed my baby chicks a ripe banana as a treat, and they love it! I have 18 chicks, and I give them one banana every day, by hand. You can use this or not........The adults like it, too. Klingoncowboy4 19:48, 30 April 2007 (UTC)

I will second this, my chickens actually fight over banana's and will eat skin and all. My chickens enjoyed a ripe banana today, peel and all.

I will also second this, (or third it), my chickens love bananas. A tasty treat for them.

Cautionary Note: Aren't banana skins loaded with pesticide (except organic, one assumes)?

Our chickens go crazy for bananas.

I grind up corn stalks and sun flower plants they love it. I read somewher to give them fish raw or cooked?

my chickens won't touch any citrus fruits, love cabbage raw and bacon rinds... they love meat but i refuse to give them any poultry products. i don't think it's healthy.

My chickens love watermelon! They eat everything but the outside skin, even the green part that we don't eat. They also love tomatoes.

We nursed a very sick chook back to health, one of the things she really enjoyed was mashed banana.

MY CHICKENS DO NOT EAT CELERY OR BROCCOLI

I also feed my chickens banana, they all love them!!!

While I didn't attempt the peel, mine go nutso over really ripe bananas.

My chickens love the vegetable mash mix i make for them, I juice fruits and vegtables for myself and the pieces that are on the ends like celery, spinish stems, parsley stems, very ripe banana, grapes that on a little too soft for me to want, they all go into the blender with some juice and then i add mash to this juice mixture to make it the consitency of crumble. I use up scraps that are very healthy for them and they love the mix.Icre8arch (talk) 23:07, 20 November 2010 (UTC)

title: Talk:Raising Chickens/Feeding


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Wikijunior:Solar System/Solar System

Do you ever wonder about the things in the sky—the Sun, the Moon, the stars? People have been watching the sky for a long time, trying to figure out what is out there. We keep coming up with new ways to learn more about outer space.

Planets are big balls of rock or gas that move around stars. We live on one we call the Earth, which moves around a star we call the Sun. There are at least seven other planets moving around the Sun and a lot of other smaller things as well. All these things together are called a system. The Latin word for the Sun is Sol, so we call this system the Solar System. Far beyond our own Solar System are stars, bodies like the Sun but in some cases much bigger.

Thousands of years ago, a man named Aristarchus said that the Solar System moved around the Sun. Some people thought he was right, but many people believed the opposite: that the Solar System moved around the Earth, including the Sun (and even the other stars). This seems sensible because the Earth doesn't feel as if it's moving, does it?About 500 years ago, another man named Copernicus said the same thing as Aristarchus: that all the planets moved around the Sun and the stars were fixed in space. This time, more people agreed, but there were still people who thought the opposite. Then, about 100 years later, a man called Galileo Galilei began looking at the sky with a new invention: the telescope. He showed that it was very likely that all the planets moved around the Sun. This time, even more people thought Galileo may be right and that the Earth really did move around the Sun. Soon, more and more people started using telescopes to study the sky. However, there were still some people who thought Galileo was wrong, and he was even arrested and taken to court for lying. All the people who believed him began to learn how the planets and the other things in the Solar System moved so they could prove that he was not lying. Thousands of years after Aristarchus, people finally said "Okay, the Earth does move around the Sun". Galileo couldn't be called a liar anymore.

We can use very large telescopes to see what has happened to other stars. We can compare pictures of distant stars with pictures of our own star, the Sun. We live in exciting times because, for the first time, we have sent people into space, and we also have telescopes in space. These telescopes in space take thousands of pictures of the planets, our sun, and the distant stars. On Earth, people use the photos to learn about all the different things in the Solar System and they try to explain how the Solar System began. We even have a robot on the red planet Mars that moves around, and people on Earth tell it where to go and what to photograph. We also want to know what will happen to the Earth and the Solar System in the future.

What is in the Solar System?
At the center of the Solar System is the Sun. It is a star, like the billions of other stars in the sky. The other stars are very, very far away, so they look tiny. The Sun is important to us because it gives us heat and energy that allows life. None of the life on Earth could exist without the Sun.

The rest of the things in the Solar System orbit (travel around) the Sun. The planets are the largest of these. Each planet is a little like the Earth. But the planets are also very different from each other.

Many of the planets have moons. A moon orbits a planet. Mercury has no moons, and neither does Venus. Earth has one. Saturn has more than 80!

The planets closest to the Sun are called the inner planets. These are Mercury, Venus, Earth, and Mars. Then comes a big ring of asteroids, chunks of rock much smaller than planets. This ring is called the asteroid belt. Within the asteroid belt, there is a dwarf planet (smaller than a normal planet) named Ceres. Then come the outer planets: Jupiter, Saturn, Uranus, and Neptune. Farther out there are two dwarf planets, Pluto and Eris.

The planets have the names of Roman gods that were worshipped by people thousands of years ago, though no one believes in them now. Did you know that some days of the week are also the names of ancient gods? Saturday means "Saturn Day". Thursday means "Thor Day". Thor was a Viking god and the son of Odin. Monday and Sunday simply mean "Moon Day" and "Sun Day". Some of the months are also named after Roman gods. The month of "March" is named after the Roman god "Mars"—he was the god of War!

Beyond the orbit of Neptune is another big ring of things like the asteroids, called the Kuiper belt. Kuiper (said "KYE-per") was the last name of the person who first wrote about it. Most of the things in the Kuiper belt are hard to see through telescopes.

After the Kuiper belt comes the Oort cloud. Scientists think this is where comets come from. It is very far away, many times farther away than Pluto is from the Sun (over a thousand times). It is near the edge of the Solar System. (Yes, "Oort" was the last name of the person who first wrote about it.)

In between all the other things is dust. The pieces of dust are very far apart, but they shine in the light of the Sun. Before dawn, in September or October, they glow in the East. We call this the zodiacal glow or zodiacal light.

When pieces of space dust hit the Earth's atmosphere, they burn brightly. We call them shooting stars or meteors.

The Sun creates solar wind—a kind of gas that blows away from the Sun into space. This gas travels out past the planets into outer space. The edge, where the solar wind meets the wind from other stars, is called the heliopause. That is about 100 times as far from us as the Earth is from the Sun. Beyond that, there is a lot of empty space. The nearest star to our Sun is thousands of times farther away than the size of the entire solar system. The Universe is a really huge and empty place!

What holds it together?
Why do all of the planets orbit the Sun? Why do moons orbit planets? Why doesn't the Sun move away and leave the planets behind? The answer to all of these questions has to do with gravity. Gravity is a force that is a property of mass. It pulls things together.

We don't notice the pull from the Sun because it also pulls on the Earth by the same amount. But the Sun's gravity is strong enough to keep the Earth from shooting away. Even though the Earth is going fast, it keeps turning to go around the Sun. It is like they were tied together with an invisible string. In the same way, moons orbit many of the planets. They are kept there by gravity. The Sun itself does not sit still in space. The entire Solar System orbits the center of our galaxy. The whole thing stays together because of the force of gravity.

About mass
Everything is made of matter. The amount of matter is called mass. Two apples have twice the mass of one apple. The more mass a thing has, the more gravity pulls it, and the more its gravity pulls other objects. We don't notice the pull from an apple because it is so much less than the pull from the Earth. If you stand on the ground and let go of an apple, gravity will pull it down towards the center of the Earth. It will hit the ground. If you could throw the apple hard enough at the right angle, it would go into orbit around the Earth. That is how rockets put astronauts into orbit. If you threw the apple really, REALLY hard in the right direction, it would fly away from Earth and never come back, but our arms are not that strong.

The force of gravity from anything is strongest when very close to that thing and weaker when further from it. Scientists use weight to mean how hard gravity pulls us. Astronauts weigh less on the moon because it has less mass. It does not pull as hard. We actually weigh a tiny bit less on top of a tall mountain than we do in a lower place. This is because we are farther from most of the Earth.

Who discovered the Solar System?
Anyone who looks up at the sky enough can see seven bright objects. These are the Sun, our Moon, Mercury, Venus, Mars, Jupiter, and Saturn. People have known about them for a very long time. Ancient people thought they were related to gods. In Babylon, they named the days of the week after them. Almost everyone was sure that all these things were orbiting the Earth. They did not know we lived in a Solar System.

In about 1500, Nicolaus Copernicus figured out that the planets orbit the Sun. Only the Moon orbits the Earth. But he was afraid to say so for most of his life and only published a full account of his ideas in 1543, the year of his death. Then Galileo Galilei pointed a telescope at the sky. He found moons orbiting Jupiter. He was certain Copernicus was right, and he got in trouble for saying so. It took seventy years to convince scientists that the planets orbit the Sun. Now, almost everyone on Earth understands that we live in a Solar System. People made better telescopes and found more things in the sky—moons, new planets, and asteroids. More things, like the dwarf planet Eris, are being found today.

How have we explored the Solar System?

Before the telescope, people explored the sky with their eyes. They saw how the planets seemed to "wander" through the sky. They learned to predict where the Sun, the moon, and planets would be in the sky. They built some observatories—places for watching the sky. Observe is a more scientific word for watch. They observed the Sun and stars to tell the time of year. In China, they even knew when the moon would block the Sun. Most people thought that celestial bodies could cause war or peace on Earth.

After telescopes were first made in the early 17th century, people kept making them better. Astronomers saw that planets are not like stars. They are worlds, like the Earth. They could see that some planets have moons. They began to think about what these worlds were like. At first, some thought that the other planets and moons had people or animals living on them. They thought about how it would be to live on these other worlds. Then they made telescopes better and sent spacecraft into space, and found that there were no plants or animals on the Moon or on Mars.

Now, we can explore by going to some of the other worlds. Twelve Astronauts walked on the Moon about 35 years ago. They brought rocks and dirt back to Earth. Spacecraft flew by Venus, Mars, and the outer planets. The pictures they took showed us a lot of what we know about these worlds. Robots landed on Mars in 1971, 1976, and 1997. They took thousands of pictures of the planets. They send photos and movies back to Earth. They also check rocks to find out what they are made of.

So far, we have not found any life except on Earth. Maybe tiny, one-celled life once lived on Mars. Maybe there is life under the ice on Jupiter's moon Europa. New spacecraft are being planned to look for life on these worlds.

How was our Solar System formed?
Our Solar System is part of the Milky Way galaxy. Galaxies are big mixes of dust, gas, stars, and other things. Inside our Milky Way galaxy are clouds of dust and gas where stars are born. Our Solar System was created in this kind of cloud. A part of the cloud began to get smaller and less spread out. It formed a big, spinning disk of gas and tiny pieces of dust. This disk was thickest in the middle. The middle slowly collapsed until it became the Sun. We are still trying to learn how the planets were formed. Most scientists think that they were formed from leftover gas and dust.

This is how it could have happened. The rest of the disk continued to spin around the Sun. The tiny pieces of dust hit each other, and some of them stuck together. Next, the bits of dust slowly collected to form grains, which in turn joined to form lumps the size of gravel, then pebbles, and then rocks. The rocks crashed together into mountains. The mountains crashed together to make bigger things. These big things swept up most of the rest of the disk to form the planets, moons, and asteroids.

The Sun got hotter as it collapsed. It began to glow. The temperature at the center reached a million degrees Celsius. The Sun started to produce a lot of light and heat. This light and heat swept away most of the leftover dust and gas between the inner planets. This light and heat are the sunlight we see and feel every day on Earth.

What will happen to the Solar System?
In another five billion years, the Sun will use up most of its hydrogen fuel. It will enter the final stages of its life. The middle of the Sun will shrink down and become even hotter. The outer layer of the Sun will grow much bigger than it is now. It will form a red giant.

It will be so big that Mercury and Venus, probably Earth and maybe even Mars will be inside it. These planets will burn away. Which planets get destroyed will depend on how much mass the Sun has left. A strong solar wind will blow some of the outer layers of gas away from the Sun. The Sun will have less mass. The Sun’s gravity will be less. All of the planets will move further away from the Sun.

After it has been a red giant for a while, the Sun will start to burn helium. It will shrink down and will not be a red giant any more. It will use the helium up in about a billion years. Then it will become a red giant once again. More gas will blow away for a few hundred thousand years.

A planetary nebula will form. The nebula could last for a few thousand to a few tens of thousands of years. It will glow in the light of the Sun.

At the center, the Sun might shrink into a tiny star called a white dwarf. That kind of star is about the size of Earth. It would take about 100 of these white dwarfs, stacked end to end, to be as wide as the Sun is today. The Sun will not have any more fuel to burn. It will have lots of heat left over and will keep getting cooler and dimmer. Then its light will go out in a hundred billion years from now.

Next Topic: The Sun

title: Wikijunior:Solar System/Solar System


text:
User:Mshonle/SEAdvancedModularity

The BeOS was written in 1991. Windows XP's NT kernel in 1988. MacOS X's OPENSTEP kernel in 1994. Solaris in 1997. Linux in 1991.

=Advanced Modularity= Aspect-Oriented and Object-Oriented Software Development: A book on the effective use of AspectJ

Design Structure
Recall Baldwin and Clark, and the DSM work before then. Define what a module is, and what an interface is.

Abstraction
Some examples of poor abstractions: such as a "base class" that has two different modes such that derived classes are treated differently.

Inheritence is sometimes used as a layering mechanism, to hide concerns at the base classes.

Reasoning about programs: what private and anonymous inner classes have in common.

Crosscutting Concerns
Definition of crosscutting, tangling, and scattering.

Non-Hierarchial Constructs
AspectJ and multiple-inheritence-like interface introductions.

The Eclipse IAdaptor model allows for some nodes in an inheritence hierachy to have properties, but avoids that property from being

System Level Abstractions
Principle of Locality (i.e. VM and good replacement algorithms) crosscut our compilers and hardware systems. It's improved programmer productivity, and is largely invisible.

Garbage collection is similar, though it "pokes out" a little more than VM does. You still might have to know about the mark and sweep process, and for canoncialized pairings, you need to know what a weak reference is. In other cases, you need to know what a soft reference is.

title: User:Mshonle/SEAdvancedModularity


text:
Talk:Primary Mathematics/Factors and Primes

What practical purpose do Factors and Primes serve?


text:
Raising Chickens/Keeping your chickens happy

Keeping your chickens happy is very easy to do. If you have a big enough pen then you will already have very happy chickens. There are also many things to can do to keep them even happier.

Build Roosts

Building roosts is easy to do. All you need are some thin poles and wire. Wooden poles work best as they are most like what a chicken would find naturally. One method that works is the use of poplar trees as poles. If you are using poplar (or similar tree) then use young saplings. Trees that are around 5 years old are best. When selection used trees that are about the thickness of a broom handle. In the case of poplar don't worry if you are killing the tree. Poplar Trees reproduce by sending up shoots from their roots as well as seed. Even if you do end up killing a poplar tree in a couple of years more will grow to replace it. When you have your poles, make sure that they are the right size to fit in your shelter. Adjust size as needed then use your wire to tie that together so that they form a ladder that covers the width of the shelter. Your roosts should be fairly tall and strong. From experience, some of our contributors have found that chickens prefer to sleep in their roosts

Scatter food (for them to find)
To do this all you have to do is scatter your chickens' food around and let them follow their natural instincts. In the jungle, where chickens originally came from, wild chickens spent their day looking around for things to eat. Scattering their food around their pen allows them to do this in a safe (no predators and guaranteed food) setting.

If you have hay down to keep the mud away try scattering some corn in the hay. This results in the chickens spreading the hay around while being entertained (IF you do not let them out).

Give them scraps you normally wouldn't
This method requires that you give your chickens scraps that aren’t unhealthy for your chickens but they still won't eat. These are scraps that, for whatever reason, your chickens would rather (or can only) play with instead of eat. A good example is Orange peels. Chickens find it difficult to eat these because they are too tough. However, if your chickens are bored then giving these to them will give them something to play with. Orange peels won't cause harm to your chickens and as such are safe. For a complete list of foods that Chickens normally don't eat see Feeding.

Also, if your chickens don't have the ability to free range for their nutritional needs, you must provide them with grit (ground stone) to aid them with digestion. Birds lack the ability to chew their food so must crush it in the gizzard, a strong muscle that uses grit to break apart the grain they consume.

Other methods
For a list of methods that have worked for other people (or to post your own) go to the discussion page for this chapter. Keep a small pail under your kitchen sink and add tasty bits to feed later to your chickens. You can save carrots, bits of celery and lettuce, etc. If you just throw them on the ground inside their pen, they will rush over to investigate and enjoy a treat that is more interesting than their regular chicken food, but make sure the food isn't rotten or spoiled.


text:
Talk:Raising Chickens/Keeping your chickens happy

Other methods for entertaining chickens
Post your methods for keeping your chickens happy here. Klingoncowboy4 05:51, 3 Jul 2005 (UTC)

Feed 1 tbs. white millet per bird as a treat.

My chickens LOVE cottage cheese low fat type with  a little Quaker oats  sprinkled on top.

Simple, corn and plenty of it82.38.78.129 13:57, 25 April 2006 (UTC)

Depending on the kinds of chickens you have, you may be able to get them to come near you and you can hold them and pet them as well. Some of them just run away from you when you try to get closer to them. I missed the kind that I had when I was in Luang-Prabang, Laos. Some of them are very sportive and you can let them fight a little for exercises. Please let them fight for fun only and make sure that it's not for gambling or for serious killing of one another !

Mine seem to like me cracking sunflower seeds and chucking them in the pineneedles to find.

Hand raising chicks
Handling chicks is the best way have tame friendly adult chickens. Friendly chickens are much easier to handle and care for than shy or unfriendly chickens, however if you are raising your chickens for meat (and not as pets or for egg production) having an up-close and personal relationship with your poultry may not be a good idea. Friendly chickens don't just run up to you when you have food; they will perch on your lap or shoulder and coo sweetly to you,because their always up for a snuggle ;D.

Take into account that breeds such as Rhode Island Reds seem to be the most playful, however they are high strung, sometimes aggressive and are never as friendly and cuddly as Buff Orpingtons or Wyandottes. Roosters and cockerels are naturally more aggressive than pullets and hens.

When they are very small you can scoop the chicks up and hold them in the palm of your hand, be sure to keep them warm and always be very gentle with chicks before their feathers grow in. Do not squeeze chicks. It's best to sit on the floor and hold the chick low so that if it walks off of your hand it will land softly.

As the chicks grow larger you can play with them much more, be gentle and patient. Chicks are capable of running very fast and can cram themselves into very small spaces; be sure to play with them where they cannot run under (or into) furniture or small openings or where other animals might trap them (even the friendliest house cat can be a serious threat to a small chick.)

In general most chickens like exercise and stimulation so you can be creative, use a bell caged in a plastic ball or dangle parakeet toys for chicks and larger cockatoo and cat toys for fully grown chickens. One fun way to give treats to your chicks is to drill small holes in a plastic ball or egg (like the kind used for Easter candy) and put a little chick starter inside, as they grow older you can put corn, carrot peelings, clean crushed shell, or left overs from your meals inside just to keep things interesting. Some chickens get quite possessive of their favorite toys so if you have more than one chicken be sure to have plenty toys to go around.

If you have too many chicks to hold then usually a handwarmer under some small towels will provide enough warmth for the rest.

Any coop needs roosts.
This silly page says the following "WARNING: Roosts should only be built in for shelters that are large enough for you to stand in comfortably."

That has to be the most ridiculous thing I have ever heard. Chickens instinctively want/need to roost. The height of the coop is irrelevant to that need. 216.183.196.254 (discuss) 03:04, 11 April 2012 (UTC)


text:
Talk:Raising Chickens/Finding a Hatchery

Your Hatchery
Add your hatchery here Klingoncowboy4 06:08, 3 Jul 2005 (UTC)

Alturnative
An alternative to finding a hatchery is to find already grown hens/roosters. Many small growers are ready to give them away (free/barter/cheap) at the end of the laying season. Obviously your selection is limited to what's available, but this method saves the expense and trouble of dealing with chicks. Keep an eye on the local paper or bargain sheet. You can also ask anyone with a flock if they'd be willing to part with a few birds. Depending on the purpose of your flock, someone else's culls might be just the right birds for you. Be careful that you pick up healthy birds.

When you introduce new birds to your established flock, it won't take long for new and old birds to integrate and establish their "pecking order." Not to worry, it looks nasty at first but they quickly work it out. If two of them insist on constantly fighting, they'll be so busy with each other that you can easily pick up and move one of the birds to another part of the pen. If you're adding a grown rooster to a flock that already has one, I recommend avoiding a new one that's been the only or head honcho at his old place. Pick the second or third in the pecking order if you have a choice so your current head rooster can get along with him.


text:
Calculus/Area

Introduction
Finding the area between two curves, usually given by two explicit functions, is often useful in calculus.

In general the rule for finding the area between two curves is

$$A=A_{\rm top}-A_{\rm bottom}$$ or

If f(x) is the upper function and g(x) is the lower function

$$A=\int\limits_a^b \bigl(f(x)-g(x)\bigr)dx$$

This is true whether the functions are in the first quadrant or not.

Area between two curves
Suppose we are given two functions $$y_1=f(x)$$ and $$y_2=g(x)$$ and we want to find the area between them on the interval $$[a,b]$$. Also assume that $$f(x)\ge g(x)$$ for all $$x$$ on the interval $$[a,b]$$. Begin by partitioning the interval $$[a,b]$$ into $$n$$ equal subintervals each having a length of $$\Delta x=\frac{b-a}{n}$$. Next choose any point in each subinterval, $$x_i^*$$. Now we can 'create' rectangles on each interval. At the point $$x_i*$$, the height of each rectangle is $$f(x_i^*)-g(x_i^*)$$ and the width is $$\Delta x$$. Thus the area of each rectangle is $$\bigl[f(x_i^*)-g(x_i^*)\bigr]\Delta x$$. An approximation of the area, $$A$$, between the two curves is
 * $$A:=\sum_{i=1}^n \Big[f(x_i^*)-g(x_i^*)\Big]\Delta x$$.

Now we take the limit as $$n$$ approaches infinity and get
 * $$A=\lim_{n\to\infty}\sum_{i=1}^n \Big[f(x_i^*)-g(x_i^*)\Big]\Delta x$$

which gives the exact area. Recalling the definition of the definite integral we notice that
 * $$A=\int\limits_a^b \bigl(f(x)-g(x)\bigr)dx$$.

This formula of finding the area between two curves is sometimes known as applying integration with respect to the x-axis since the rectangles used to approximate the area have their bases lying parallel to the x-axis. It will be most useful when the two functions are of the form $$y_1=f(x)$$ and $$y_2=g(x)$$. Sometimes however, one may find it simpler to integrate with respect to the y-axis. This occurs when integrating with respect to the x-axis would result in more than one integral to be evaluated. These functions take the form $$x_1=f(y)$$ and $$x_2=g(y)$$ on the interval $$[c,d]$$. Note that $$[c,d]$$ are values of $$y$$. The derivation of this case is completely identical. Similar to before, we will assume that $$f(y)\ge g(y)$$ for all $$y$$ on $$[c,d]$$. Now, as before we can divide the interval into $$n$$ subintervals and create rectangles to approximate the area between $$f(y)$$ and $$g(y)$$. It may be useful to picture each rectangle having their 'width', $$\Delta y$$, parallel to the y-axis and 'height', $$f(y_i^*)-g(y_i^*)$$ at the point $$y_i^*$$, parallel to the x-axis. Following from the work above we may reason that an approximation of the area, $$A$$, between the two curves is
 * $$A:=\sum_{i=1}^n \Big[f(y_i^*)-g(y_i^*)\Big]\Delta y$$.

As before, we take the limit as $$n$$ approaches infinity to arrive at
 * $$A=\lim_{n\to\infty}\sum_{i=1}^n \Big[f(y_i^*)-g(y_i^*)\Big]\Delta y$$ ,

which is nothing more than a definite integral, so
 * $$A=\int\limits_c^d \bigl(f(y)-g(y)\bigr)dy$$.

Regardless of the form of the functions, we basically use the same formula.

title: Calculus/Area


text:
MediaWiki:Sidebar

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title: MediaWiki:Sidebar


text:
Statistics/Summary/Averages/Harmonic Mean

Harmonic Mean
The arithmetic mean cannot be used when we want to average quantities such as speed.

Consider the example below:

Example 1: The distance from my house to town is 40 km. I drove to town at a speed of 40 km per hour and returned home at a speed of 80 km per hour. What was my average speed for the whole trip?.

Solution: If we just took the arithmetic mean of the two speeds I drove at, we would get 60 km per hour. This isn't the correct average speed, however: it ignores the fact that I drove at 40 km per hour for twice as long as I drove at 80 km per hour. To find the correct average speed, we must instead calculate the harmonic mean.

For two quantities A and B, the harmonic mean is given by: $$\frac{2}{\frac{1}{A} + \frac{1}{B}}$$

This can be simplified by adding in the denominator and multiplying by the reciprocal: $$\frac{2}{\frac{1}{A} + \frac{1}{B}} = \frac{2}{\frac{B + A}{AB}} = \frac{2AB}{A + B}$$

For N quantities: A, B, C......

Harmonic mean = $$\frac{N}{\frac{1}{A} + \frac{1}{B} + \frac{1}{C} + \ldots}$$

Let us try out the formula above on our example:

Harmonic mean = $$\frac{2AB}{A + B}$$

Our values are A = 40, B = 80. Therefore, harmonic mean $$= \frac{2 \times 40 \times 80}{40 + 80}= \frac{6400}{120} \approx 53.333$$

Is this result correct? We can verify it. In the example above, the distance between the two towns is 40 km. So the trip from A to B at a speed of 40 km will take 1 hour. The trip from B to A at a speed to 80 km will take 0.5 hours. The total time taken for the round distance (80 km) will be 1.5 hours. The average speed will then be $$\frac{80}{1.5} \approx$$ 53.33 km/hour.

The harmonic mean also has physical significance.


text:
Talk:Ordinary Differential Equations

The Wikibook for Calculus already covers some portion of Diffrential equations, including a rather complete introduction to ODE. I think it would save time and effort to expand on that section, and make DE a part of that book. Over a period of time, other higher level books would also be integrated into calucus (such as series, complex analysis,etc).

Sorry for not reading this sooner, I was on vacation for the 4th. I'm not sure I agree this should be part of another book, although I'm willing to discuss it further. DE is a rather large and complex topic, easily a college semester even with barely touching partials. I think adding it into one giant book would be doing a disservice to both subjects- it would make the calculus book so huge as to be daunting to readers, and make the DE part a side note when it deserves more attention. I guess my mindset is more of the Unix philosophy as applied to books- do one thing, and do it well. Tieing things together into courses of study (calc, then DE, then linear algebra (or whatever order)) is the job of a higher order layer.

I took a quick glance at the DE section of the Calculus book. Its well written and covers a lot of ground. The problem I have with it is that it doesn't *teach* DE. Its a problem I have with a lot of wikibooks. Its a good reminder, if I wanted to review the subject it would work well. But if I had never solved a DE before and was studying the subject for the first time, I would be utterly lost. It has few examples, no practice problems and answers, little explanation of why things worked, no discussing of the theory behind the methods, nothing of the practical applications. It reads more like an encyclopedia entry than a book. Which makes sense, given the nature of wikibooks springing from wikipedia. And its better than the average wikibook out there, having read many that looked like powerpoint slides. But still of low use as a classroom or self teaching aid.

Which brings us to another issue on adding this DE to the calculus book. I don't want the book to look like the standard wikipedia style. I don't like the standard style, being too much encyclopedia and not enough book. Given that I won't be using the same style, I'm not sure that it would be a good idea to assimilate the content into one book. Within a book, IMHO, one ought to make an attempt to keep the style of the information the same. To do otherwise is confusing. And while I have no doubt my style will have its own deficiencies and I'm happy to listen for impovements, I doubt you'll be able to convince me to switch to standard wikibook style.

--Gabe Sechan July 5, 2005 22:01 (UTC)

Just laying out some ideas for a brief reformation, im going to write some things on the formation of differential equations before the tackling of the concept of a solution so as to provide what I hope will be a more intuitive and understanding approach.Robert Carr 03:38, 18 January 2006 (UTC)

It's a shame to see this book neglected -- it would be a really nice resource to have an online book on DEs. I think I'll write some content for it. I've already written Variation of Parameters (under Constant Coefficients) and maybe I'll also add something about Laplace transforms, which are really fun and powerful. Perhaps I'll even do a section on series solutions if I'm feeling bold.... N Shar 05:17, 31 January 2006 (UTC)

Please do. I'm sorry the book has become neglected as well- I just don't have time to add to it these days. And on top of that, I lack the confidence in some of the more advanced material- I am not a math professor. As the material gets more advanced I felt more like I was regurgitating source books than I was writing from my understanding of the material. --Gabe Sechan 19:22, 31 January 2006 (UTC)

Relationship of this book with the Wikipedia entry on Ordinary Differential Equations
Reading the current version of the Wikipedia entry on ordinary differential equations, it seems to me that much of that material belongs in a textbook, rather than an encyclopedia entry. I think the encyclopedia should have definitions and motivation for studying the material. I have written a comment to that effect on the wikipedia article, and I'm in the process of writing some of that material for the wikipedia article.

Now as far as the wikibook is concerned, I think the title shhould be "Ordinary Differential Equations", because that describes the content. My background is in partial differential equations, so I'd like to advance that side of the wiki enterprise, but I think ODE comes first logically. I'm now retired with some time on my hands, so I'd like to help with any or all of these enterprises. So far I haven't been able to get a wikibooks ID, but my wikipedia ID is "donludwig". Email is ludwig@math.ubc.ca 154.5.94.9 17:46, 23 February 2006 (UTC)

Book Development
I'm currently studying Diff EQ and would like to contribute to this book. This is the second time I've taken this course, and I feel that there are many students out there that would benifit from a free resource that could explain topics from a non-textbook-writer point of view. More importantly, I'd like to expand the example problems to cover as many examples as possible since this is the main way of learning any subject: practice. Please contact me so that we can discuss further development at curtwulf at gmail dot com. Thanks. Curtwulf 12:23, 29 March 2006 (UTC)

Definitions
Arnold defines an ODE as follows. An ODE is a process evolving in time that has the following 3 characteristics: (1) deterministic (2) finite dimensional (3) differentiable. where deterministic means that the entire past and future of a process is determined by its initial value. finite dimensional means that the set of all possible states of your process (the phase space) can locally be parametrized by finite many real numbers (eg.: a sphere can locally be parametrized by two real numbers, so does the plane, the real line, etc). Differentiability means that the time evolution processes can be described by an equation that is differentible.

I like this approach to ODE's by Arnold better then the one normaly found at books because it is more conceptual.

Response: With all due respect to Arnold, that definition is too narrow for many practical purposes. It focuses on "processes evolving in time" which is not the only situation where ODEs arise. For example, it excludes boundary value problems in which case the description "the entire past and future of a process is determined by its initial value" makes no sense.

Furthermore, the requirement (3) is too restrictive. Consider, for instance, the differential equation y'(t) + y(t) = f(t) where f is a step function. Such equations arise all the time in electronic circuits; the step in f corresponds to throwing a switch. The solution y is continuous but not differentiable. Of course, to make sense of the differential equation, we need to view it as an integral equation, as in:

y(t) = y(0) + int0t [ f(t) - y(t) ] dt

which is what one does when proving the existence and uniqueness theorems anyway.

-- rr

Reformat
I'd like to create a standard layout for accessing the examples, problems, and answers, like at the end of the page explaning the topic so the confusion in the chapter on First Order Equations doesn't happen.

Katdai (talk) 19:02, 24 May 2008 (UTC)katdai

Calculus category
Given that most universities list this course as "Calculus ##" (usually IV), I feel like it would make sense to include this in the Calculus category. I didn't find out about this book existing until looking at the discussion of the DE section of the Calculus textbook, and the first place I looked for it was in the Calculus section. Support? XarBiogeek (talk) 08:34, 17 February 2010 (UTC)

 * My experience is that the topics covered at most universities in a course such as "Calculus IV" would not go into the depth that is aimed for in the current book. So in general I suppose I don't think it would work to include the book in the Calculus category.  Maybe we could provide a link from the Calculus subject to the subject on Differential equations to aid in people finding this book.  Out of curiosity how did you calculus book that lead you here.  It has always been a question as to how our readers find the books they are looking for. Thenub314 (talk) 00:19, 6 October 2010 (UTC)

Books title
I am interested in renaming this book, as it's current title seems a bit too broad to me. I was thinking something along the lines of "Ordinary Differential Equations", but maybe working in "Introduction", "Introductory", etc. What do other people think? Thenub314 (talk) 00:32, 6 October 2010 (UTC)

Roadmap
Hi, I'm new to editing this book. It would be extremely beneficial if there were a plan regarding what to add. That is especially true since there are a limited number of volunteers contributing, and they each have a limited amount of time to give. Currently the "Roadmap" page is only a red link from the table of contents.

To move this book toward completion we should focus on finishing the essentials before adding peripheral material; consider what you would find in an elementary differential equations book for college undergraduates.

Thank you all. I hope this book grows quickly!

AUN4 (discuss • contribs) 21:07, 21 January 2012 (UTC)

Formation of Differential Equations
I think this section of the book should go. It does not add to the study of the subject, and is distracting for a pedagogical prospective. From a practical point of view it is backwards, as usually you are looking for the unknown function that solves an ODE. Overall it just doesn't add to the text. If there are no objections I will remove it. Thenub314 (talk) 16:49, 12 April 2012 (UTC)
 * In absence of any objections, I have deleted the section. Thenub314 (talk) 15:01, 28 April 2012 (UTC)

title: Talk:Ordinary Differential Equations


text:
File:Maya-nodes-connectedexample.png

Maya example of how the gamma node should be connected with the file and the IBL node

title: File:Maya-nodes-connectedexample.png


text:
Cookbook:Nem Assembly

Nem is a Vietnamese term referring generally to a variety of rolls, usually wrapped in rice paper. They may contain a variety of fillings and may be deep fried. The technique for assembling and rolling nem is illustrated below.

title: Cookbook:Nem Assembly


text:
File:Maya-selected-all-geometry-outliner.png

Maya, all geometry groups selected in the outliner


text:
File:Maya-lighter-first-render.jpg

Maya render 1 of the lighter

title: File:Maya-lighter-first-render.jpg


text:
Talk:Japanese/Lessons/Days

Untitled
三日間前 (さんにちかんまえ) is wrong. The correct one is 三日前 (みっかまえ). And also 十日間　(じゅうにちかん) is to be 十日間(とおかかん). One exception exists when saying `for a day': 一日(いちにち). いっか ikka is to be いちにち ichinichi. --K12u 3 July 2005 16:25 (UTC)

title: Talk:Japanese/Lessons/Days


text:
Software Engineers Handbook

The purpose of this online collaboration is to provide to software engineers, software developers, computer scientists, and information technology professionals a good place to look when they are starting something new. The introductory material would be given here, including vocabulary necessary to search the web effectively, and references to web sites, articles, and texts for more in depth coverage.
 * About to try a new programming language? See the language dictionary.
 * Have an interview in a new industry? See the sector pages.
 * Switching to another operating system? See the operating system pages.
 * Been asked to put together your configuration management strategy for your project? See the supporting processes pages.
 * Don't find what you need? Create a page or request one using the talk page
 * Please contribute to pages within your area of expertise.

Life Cycle

 * Development Methodologies
 * Extreme Programming
 * Traditional Waterfall

 * Problem Analysis

 * Requirements
 * Software Requirements Specification

 * Design
 * Choosing an Algorithm
 * Choosing a Data Structure
 * Large Scale Projects
 * Methodologies
 * Patterns

 * Implementation
 * Choosing a Programming Language
 * Coding Standards
 * Refactoring

 * Software Quality Assurance (SQA)
 * Testing
 * Unit Testing
 * Integration Testing
 * User-Acceptance Testing

Supporting Processes

 * Configuration Management
 * Computer-Aided Software Engineering

Software Engineering General Links

 * Software Engineering Body of Knowledge (SWEBOK)

Operating Systems

 * OS X
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RTOS - RealTime Operating Systems

 * µC/OS-II - A highly portable multitasking Real-Time Kernel, ROMable, very scalable, preemptive real-time, multitasking kernel (RTOS) for microprocessors and microcontrollers
 * uSmartX - A non-preemptive, multitasking, priority based RTOS for small foot-print embedded designs.
 * ESF RTOS - an elegant, simple, powerful, and easily customizable, object-oriented interface to kernel services, such as thread creation and synchronization.
 * Micro Itron - A japanese Operating System.

Sectors/areas of industry specialization

 * Finance
 * Imaging
 * Security
 * Automotive

Fields/areas of development specialization

 * Database
 * Embedded Systems
 * Office Automation
 * Web

Language Dictionary
Here is the language dictionary sample template. Please use it for new language entries. (Open, edit, copy, click cancel, go to the page you're adding, and paste it in the editing page. Edit to match the language being added.  And thanks for adding a new language!)

Multi-paradigm

 * Ada
 * C++
 * Perl
 * PHP
 * Python
 * C#

Object Oriented

 * Java
 * Ruby
 * Smalltalk
 * Visual J++
 * Visual Basic .NET

Procedural

 * COBOL
 * FORTH
 * Perl
 * PHP
 * PL/B
 * PL/I
 * Visual Basic

Imperative

 * ALGOL
 * BASIC
 * C
 * FORTRAN
 * Pascal

Functional

 * Erlang
 * Haskell
 * J
 * Joy
 * Lisp
 * ML
 * Ocaml
 * Qi
 * RPG

Scripting

 * bash
 * csh
 * rexx

Mini

 * bc

Markup Languages

 * HTML
 * XML
 * Wikitext

Code Generators

 * Rhapsody
 * Rational Rose Realtime
 * Tau Telelogic

Assembly (template)

 * Burroughs B5700
 * DEC PDP-11
 * IBM
 * IBM 360
 * IBM 709
 * IBM 1401
 * x86
 * FASM
 * GAS
 * GoAsm
 * HLA
 * Ideal
 * MASM
 * NASM

Logical

 * Prolog
 * Mercury
 * Oz

Concurrent Constraint

 * Janus
 * ToonTalk

title: Software Engineers Handbook


text:
Category:Rhubarb recipes

Recipes involving rhubarb.

title: Category:Rhubarb recipes


text:
Software Engineers Handbook/Language Dictionary/Sample Template

Type

Execution Entry Point

General Syntax

Comments

Variable Declarations

Method Declaration/Implementation

Scope

Conditional Statements

Looping Statements

Output Statements

Error Handling/Recovery

Containers

Algorithms

Garbage collection

Physical Structure
<Describe how the files, libararies, and parts are typically divided and arranged.>

Tips
<Please include tips that make it easier to switch to this language from another language.>

Web References
<List additional references on the web. Please include for what level reader the references are appropriate. (beginner/intermediate/advanced)>

Books and Articles
<List additional books and articles that may be helpful. Please include for what level reader the references are appropriate. (beginner/intermediate/advanced)>


text:
Portuguese Grammar

Última flor do Lácio, inculta e bela,

És, a um tempo, esplendor e sepultura:

Ouro nativo, que na ganga impura A bruta mina entre os cascalhos vela...

Amo-te assim, desconhecida e obscura.

Tuba de alto clangor, lira singela,

Que tens o trom e o silvo da procela,

E o arrolo da saudade e da ternura!

Amo o teu viço agreste e o teu aroma

De virgens selvas e de oceano largo!

Amo-te, ó rude e doloroso idioma,

em que da voz materna ouvi: "meu filho!",

E em que Camões chorou, no exílio amargo,

O gênio sem ventura e o amor sem brilho!

Olavo Bilac

Introduction

 * About this Wikibook
 * About Portuguese language
 * About Portuguese speaking countries
 * Grammar overview

Alphabet & Phonology

 * Alphabet
 * Orthography
 * Pronunciation
 * Soft Vowels
 * International Words

Morphology

 * Noun
 * Article
 * Adjective
 * Pronouns
 * Tables
 * Verb
 * Tables
 * Preposition
 * Conjunction
 * Interjection
 * Word Formation

Advanced grammar

 *  Crase

More on History

 * Romance Languages
 * Iberia and Portuguese
 * Around the World

Variations

 * Portuguese Standard Language vs. Brazilian Standard Language
 * European Colloquial Portuguese
 * Brazilian Colloquial Portuguese
 * African Colloquial Portuguese
 * Portuguese in East Timor

title: Portuguese Grammar


text:
Cookbook:Rhubarb Pie

| Rhubarb Recipes

This rhubarb pie is fairly sweet, but also quite tangy. It is best served warm with a scoop of vanilla ice cream.

Ingredients

 * 1 recipe Flaky Pie Crust
 * 5 cups (40 oz / 2 ½ lb / 1100 g) rhubarb stalks
 * 1 ½ cups (12 oz / 340 g) white granulated sugar
 * ¼ cup (2 oz / 60 g) cornstarch or tapioca pearls
 * ½ tsp salt

Crust

 * 1) Prepare the flaky pie crust and refrigerate while preparing the filling.

Filling

 * 1) Clean and trim the rhubarb stalks.
 * 2) Cut the stalks into ½–1 inch (1.25–2.5 cm) sections.
 * 3) Add sugar, cornstarch or tapioca, and salt.
 * 4) Stir until rhubarb is evenly coated with dry ingredients.

Forming and cooking the pie

 * 1) Follow the instructions in the flaky pie crust recipe.
 * 2) Place pie on lowest rack in oven. Bake for 15 minutes. Reduce oven temperature to 350 °F (175 °C), and continue baking for 40–45 minutes.
 * 3) Serve warm or cold.

Notes, tips and variations

 * If cornstarch is used as the thickener, the pie requires a longer cooling time before the filling gels.
 * Try using a whole egg in the filling.
 * This cookbook also has a recipe for strawberry rhubarb pie.

title: Cookbook:Rhubarb Pie


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File:Maya-blinn-black-plastic.png

Maya Blinn black plastic material

title: File:Maya-blinn-black-plastic.png


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Software Engineers Handbook/Language Dictionary/C++

C++
C++ is an Multi-paradigmed programming language derived from C.

Type
C++ is a full, Multi-paradigmed programming language implementing the following paradigmen: generic (template metaprogramming), imperative and object-oriented (class-based)

Execution Entry Point
An executable starts with the main method.

General Syntax
The typical statement is completed by a semi-colon. For the assignment of b to a use:

Comments
Block comments are specified by a starting /* and ending */ They can span multiple lines.

Variable Declarations
Declarations can appear anywhere in the implementation.

Declare i as an integer:

Here are two ways to declare i as an integer and give it an initial value of 0:

Method Declaration/Implementation
Methods are declared by specifying the interface for the method. It is often declared within the scope of a class.

Method implementation repeats much of the same information

IMPORTANT POINT A beginner in C/C++ might get confused about the distinction between how pointers are declared in a function prototype vs. how the function is defined. For example, if my_function does not return anything, but accepts one floating point input, its function prototype looks as follows:

However, if the variable my_var is defined to be a pointer to a float, for example:

Then the manner in which my_function is invoked is as follows:

Beginners sometimes get confused about the fact that a "*" is used to tell the compiler in a prototype statement that a variable is a pointer, but a "*" is not syntactically used during invocation of a function that accepts a pointer as input.

Scope
Scope is defined by curly braces.

Conditional Statements
If and only if A is equal to B assign C to D, otherwise, assign E to F.

or

Alternatively, a switch statement can be used for multiple choice operations. This sample converts a number input to text.

Looping Statements
This code counts from 0 to 9, adding up the contents of the array.

This code repeats until the number 4 is found. If this runs off of the end of the array, there could be a problem.

This code increments the counter before the check is made, so that it starts with element 1.

Output Statements
or

Containers
The standard template library has a variety of containers including vector, bit-set, list, map and multi-set.

Algorithms
The standard template library has a variety of algorithms including sort, remove_if, and find_if.

Garbage collection
Garbage collection is manual.

Physical Structure
Generally the interfaces are defined in header files, often *.h. The implementation files are often named *.cpp. Useful collections of classes can be compiled into libraries, often *.dll, *.a, or *.so, which can be compiled into executables (statically linked) or used on the fly (dynamically linked).

Tips
Don't confuse these two:

Often using the one you don't want will compile, and will produce results you did not expect.

A good practice is to write; if(CONSTANT == variable) rather than if(variable == CONSTANT) since the compiler will catch; if(CONSTANT = variable) but not if(variable = CONSTANT).

Arrays start with index 0.

Web References

 * C++ wikibooks

Books and Articles

 * Bruce Eckel, Thinking in C++, Volume 1: Introduction to Standard C++ ISBN 0139798099. It has helped many people make the leap from C to C++. It is available for free online at Bruce Eckel's site.
 * Nicolai M. Josuttis, The C++ Standard Library : A Tutorial and Reference ISBN 0201379260. It contains lengthy and advanced discussions on the standard template library conatiners and algorithms.
 * Stanley B. Lippman, Josée Lajoie & Barbara E. Moo, C++ Primer ISBN 0321714113. This is a very thorough introduction to C++, taking nearly 1000 pages to introduce programmers to C++.
 * Andrew Koenig & Barbara E. Moo, Accelerated C++ ISBN 020170353X. This is another introduction to C++, but stresses the use of the STL. It is a quite compact introduction, with a steeper learning curve better suited for those who already know another programming language.
 * Scott Meyers, Effective C++ ISBN 0321334876, More Effective C++ ISBN 020163371X, Effective STL ISBN 0201749629. Meyers' series of books contain the best C++ practices, from class design to minimising compilation dependencies.
 * Herbert Schildt, C++: The Complete Reference ISBN 0072226803. It contains dictionary-like listings of code syntax and usage.  The structure does not make it useful to learn the language from scratch.  However, it could be very useful when switching from a similar language.
 * Bjarne Stroustrup, The C++ Programming Language ISBN 0201889544. Written by the creator of C++, it covers everything from the core language to the standard library. The book itself has over 1300 pages.


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File:Maya-lighter-with-materials.jpg

Maya render of a lighter with

title: File:Maya-lighter-with-materials.jpg


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File:Maya-phong-transparent-orange-plastic.png

Maya Phong material to emulate transparent orange plastic


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File:Maya-phong-chrome.png

Maya Phong material settings to emulate chrome

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User:Markus Krötzsch

As of 2008, Markus Krötzsch is the main developer of Semantic MediaWiki and a researcher in the areas of Semantic Web and knowledge representation and reasoning (especially relating to Description logics, Logic programming and Formal concept analysis).

Up-to-date information about Markus Krötzsch is to be found at his homepage http://korrekt.org.

title: User:Markus Krötzsch


text:
Bartending/Cocktails/Coquito

Coquito is a Puerto Rican coconut egg-nog served on Christmas and New year's. The drink is often served in a shot glass garnished with nutmeg and cinnamon.

Ingredients

 * 4 egg yolks
 * 6oz can cream of coconut (Coco-Lopez)
 * 12oz can evaporated milk
 * 14oz can of coconut milk or home made
 * 14oz can sweetened condensed milk
 * 4oz dark rum
 * 3 cinnamon sticks
 * 2 star anise
 * 1 cup of water
 * 1/4 tsp of whole cloves
 * ground nutmeg and cinnamon for garnish
 * 1 vanilla bean or 1 tsp vanilla extract

Directions
(NOTE: It is extremely important that you make sure there are as little clumps in the mixture as possible!)
 * 1) In the top of a double boiler, combine egg yolks and evaporated milk. Stirring constantly, cook over lightly simmering water until mixture reaches a temperature of 160 degrees F (71 degrees C). The mixture should be thick enough to coat the back of a spoon.
 * 2) First remove the seeds from vanilla skin. Hold the bean down on either end. With the tip of a paring knife, poke a hole in the top and slide it down the bean, splitting it in half lengthwise. Open it with the knife tip and scrape down, collecting the seeds on the blade.
 * 3) Start by boiling the vanilla seeds and skin (not vanilla extract), cinnamon sticks, clove and star anise in the 1 cups of water. Reduce to 1/2 cup. When the water turns yellow and has the smell and you can taste the spices, take the spices out.
 * 4) Add coconut milk, cream of coconut and sweetened condensed milk to spiced water and stir over medium heat for 3 minutes or until a slight boil. Remove and cool.
 * 5) Once cool mix in eggs, rum and vanilla extract if using extract.
 * 6) Refrigerator serve cold in shot glasses, or with ice in tumblers. Garnish with nutmeg and cinnamon.

title: Bartending/Cocktails/Coquito


text:
Cookbook:Roasted Pork Shoulder (Pernil Asado)

Ingredients:

 * 1 ea. 4 ½-pound (2.5 kg) pork shoulder
 * 1 ½ tbsp kosher salt
 * 12 medium garlic cloves, peeled
 * 1 tbsp pepper
 * 2 tbsp whole dry oregano
 * 2 tbsp fresh thyme
 * 2 tbsp olive oil
 * 2 tbsp white wine vinegar

Procedure

 * 1) Wash the pork shoulder.
 * 2) Skin side down, use a sharp knife to make incisions in different places of the pork shoulder.
 * 3) Grind together the garlic, pepper, oregano, and salt
 * 4) When done grinding, mix in oil and vinegar.
 * 5) Fill the incisions of the pork with the ground mixture. Whatever is left over rub on the outside of the pork.
 * 6) Put away in the refrigerator for 3 days. If you planned to cook it the same day, prepare the pork at least 1 hour ahead of time.
 * 7) Remove the pork shoulder from the refrigerator 2 hours before putting it in the oven.
 * 8) Preheat the oven at 350ºF (180°C) for at least 10 minutes before you begin cooking the pork shoulder.
 * 9) Cook the pork for 3½ hours.
 * 10) Raise the temperature to 375°F (195°C) and cook for 15–30 minutes until the skin is toasted and browned.


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User talk:Markus Krötzsch

Don't be shy to describe yourself, Denny Vrandečić and Max Völkel with two sencences at Wikimania05/Paper-MK2. You should also simply say that you work at a university - Wikimania is not a scientific-only conference! -- JakobVoss 3 July 2005 23:10 (UTC)

 * I will gladly add some descriptions as soon as I have the time. Since LaTeX-To-Wiki processing is somewhat cumbersome, I am still concerned with converting the paper … --Markus Krötzsch 4 July 2005 15:21 (UTC)

title: User talk:Markus Krötzsch


text:
Spanish/Reflexive Verbs

Reflexive verbs indicate that the action of the verb reflects back on the subject. In their infinitive forms, reflexive verbs end in -se.

Examples:
 * lavarse- to wash oneself
 * vestirse- to dress oneself

Conjugation requires removing the -se ending and conjugating normally. The reflexive pronouns are then placed before the conjugated form of the verb.

Lavarse
 * yo - me lavo - I wash myself
 * tú - te lavas - you wash yourself
 * él/ella/Ud. - se lava - he/she/it washes himself/herself/itself
 * nosotros - nos lavamos - we wash ourselves
 * vosotros - os laváis - you (plural) wash yourselves
 * ellos/ellas/Uds. - se lavan - they wash themselves

Vestirse
 * yo - me visto - I dress myself
 * tú - te vistes - you dress yourself
 * él/ella/Ud. - se viste - he/she/it dresses himself/herself/itself
 * nosotros - nos vestimos - we dress ourselves
 * vosotros - os vestís - you (plural) dress yourselves
 * ellos/ellas/Uds. - se visten - they dress themselves

Reflexive verbs often have to do with personal hygiene, grooming, and dressing:

 * peinarse- to brush one's hair
 * maquillarse- to make-up oneself
 * cepillarse (los dientes)- to brush one's teeth
 * bañarse- to bathe oneself

Remember that the reflexive pronoun (me, te, se, etc.) must be included with the verb, even if the subject pronoun (yo, tú, él, etc.) is not.

List of reflexive verbs:
 * aburrirse - to get bored
 * acercarse - to get close to
 * acordarse de - to remember
 * acostarse - to go to bed
 * acostumbrarse a - to get accustomed to (to get use to)
 * afeitarse - to shave
 * aficionarse a - to become interested in
 * alegrarse - to become (be) happy
 * alejarse de - to get/move away from (a person, place or thing)
 * animarse - to cheer up, to decide to/game to/become interested in doing
 * arreglarse - to get ready, to come to agreement with s.o, to dress(not get dressed) - Ella se arregla bien.;  to improve or work out right; to make due
 * apartarse de - to move away from (irse), to stray, to move aside, to withdraw or cut oneself off from
 * apoderarse de - to seize, to take possession of
 * apoyarse en - to support
 * apresurarse a - to hurry
 * aprovecharse de - to profit from, to take advantage of
 * asustarse - to get or become afraid
 * atreverse a - to dare to
 * bañarse - to take a bath
 * burlarse de - to make fun of
 * caerse - to fall (down)
 * calmarse - to calm down
 * cansarse de - to get tired of
 * casarse con - to marry
 * cepillarse - to brush (hair, teeth..)
 * colocarse de - to get/take a job
 * colocarse - to find a job, to place oneself (in a certain spot)
 * comerse - to eat something all up
 * compadecerse de - to sympathize with or take pity on
 * complacerse en - to take pleasure in
 * comunicarse - to communicate
 * conformarse con - to be conform to or comply with, to agree with, to get used to the idea or resign oneself to
 * contentarse con - to cheer up, to make do
 * convertirse en - to become, to convert, to turn into
 * cuidarse - to take care
 * darse cuenta de - to realize
 * decidirse a - to make up one's mind, to decide to
 * dedicarse a - to dedicate oneself to (profession, activity, etc.)
 * despedirse de - to say goodbye
 * desayunarse - to eat breakfast
 * despertarse - to wake up
 * despojarse de - to give up or forsake
 * desvestirse - to undress
 * dirigirse a - to go/make one's way toward; to address someone (in speech or writing)
 * disponerse a - to prepare or get ready
 * divertirse de - to have fun
 * dormirse - to go to sleep
 * ducharse - to shower
 * echarse a - to begin to (many other definitions)
 * emocionarse - to get excited
 * empeñarse en - to persist or insist on; to commit or bind oneself to
 * enamorarse de - to fall in love with
 * encargarse de - to take charge of or be responsible for; to look after or attend to; to take care of or see to
 * encogerse de hombros - to shrug (shoulders)
 * encontrarse con - to meet with
 * enfermarse - to get sick
 * enojarse - to get or become angry
 * enterarse de - to find out, to realize
 * entenderse con - to get along with; to agree or come to an agreement
 * exponerse a - to expose oneself to or run the risk of
 * exponerse de - to run the risk of
 * fijarse en - to pay attention to
 * fiarse de - to trust something or someone
 * fiarse en - to trust in something or someone
 * irse - to go (away) or to leave
 * jugarse - to play
 * lavarse - to wash (any body part)
 * levantarse - to get up
 * marearse - to get sick, to get dizzy
 * maquillarse - to put makeup on
 * meterse con - to pick on, to pick a fight with
 * meterse en - to get into
 * motivarse a- to become or get motivated to
 * moverse - to move oneself, to do or be in charge of
 * mudarse - to "move" (change residence)
 * negarse a - to refuse to
 * obsesionarse con - to be/get obsessed with
 * ocuparse de - to look after
 * olvidarse de - to forget
 * parecerse a - to look like
 * peinarse - to brush or comb hair
 * ponerse - to put on (clothing), to get dressed
 * ponerse de acuerdo - to come to an agreement with someone
 * ponerse en camino - to get on (your)way
 * portarse - to behave
 * preocuparse de - to worry about
 * prepararse a - to prepare to
 * probarse - to try on
 * quebrarse - to break (an arm, leg...)
 * quejarse de - to complain about
 * quedarse - to remain/ to stay
 * quemarse - to burn (oneself, one's body)
 * quitarse - to take off (clothing)
 * reirse de - to laugh about
 * resignarse a - to resign oneself to
 * resolverse a - to resolve oneself to
 * reunirse - to meet up or reunite
 * romperse - to break (an arm, leg...)
 * secarse - to dry (a body part)
 * sentarse - to sit down
 * sentirse - to feel
 * servirse - to help oneself to
 * suicidarse - to commit suicide, to kill oneself.
 * tratarse de - to have dealings with or associate oneself with someone
 * vestirse - to get dressed

title: Spanish/Reflexive Verbs


text:
Software Engineers Handbook/Supporting Processes/Coding Standards

Here is the wikipedia entry for coding standards.

Coding standards generally contain a set of conventions for a specific language. Items typically covered are: {    {         // code in here } }''
 * Naming conventions including:
 * how descriptive and long the names should be,
 * what the capitalization scheme should be, and
 * what the postfix and prefix conventions are.
 * Physical organization, such as Definitions shall be located in the header files. and Do not include more than one class in one file.
 * Structure conventions, such as ''Opening and closing braces shall be located in the same column like this:
 * Style guides, such as Classes containing pointers shall have a virtual destructor. It is useful to include the reasoning and references for this type of standard.
 * Legacy code guidance, such as When editing existing code, follow the coding naming and structure conventions of the existing code.

C++

 * www.possibility.com coding standard
 * www.chris-lott.org standard
 * Effective C++: 55 Specific Ways to Improve Your Programs and Designs by Scott Meyers ISBN 0321334876 is a reference for creating style guides.
 * More Effective C++: 35 New Ways to Improve Your Programs and Designs by Scott Meyers ISBN 020163371X is a reference for creating style guides.

Java

 * java.sun.com coding conventions

C

 * Gnu coding standards

Eiffel

 * ww.cs.unc.edu standard

Naming conventions
''"Always, always, always use good, unabbreviated, correctly-spelled meaningful names." -- MeaningfulName''

Popular naming conventions (naming formats) include:

 * ALL_UPPERCASE_WITH_UNDERSCORES
 * all_lowercase_with_underscores
 * CamelCase
 * uppercaseOnlyInTheMiddle
 * _UnderscorePrefixedCamelCase
 * Camel_Case_With_Underscores

For surprisingly long conversations about naming conventions, see UnderscoreVersusCapitalAndLowerCaseVariableNaming; CamelCase; CamelCase; and "Underscores vs CamelCase".


text:
File:HSE Venn1.png

Venn Diagram showing A intersec B

title: File:HSE Venn1.png