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Ceawlin of Wessex

Ceawlin (also spelled Ceaulin, Caelin, Celin, died ca. 593) was a King of Wessex. He may have been the son of Cynric of Wessex and the grandson of Cerdic of Wessex, whom the Anglo-Saxon Chronicle represents as the leader of the first group of Saxons to come to the land which later became Wessex. Ceawlin was active during the last years of the Anglo-Saxon expansion, with little of southern England remaining in the control of the native Britons by the time of his death.

The chronology of Ceawlin's life is highly uncertain. The historical accuracy and dating of many of the events in the later Anglo-Saxon Chronicle have been called into question, and his reign is variously listed as lasting seven, seventeen, or thirty-two years. The Chronicle records several battles of Ceawlin's between the years 556 and 592, including the first record of a battle between different groups of Anglo-Saxons, and indicates that under Ceawlin Wessex acquired significant territory, some of which was later to be lost to other Anglo-Saxon kingdoms. Ceawlin is also named as one of the eight "bretwaldas", a title given in the Chronicle to eight rulers who had overlordship over southern Britain, although the extent of Ceawlin's control is not known.

Ceawlin died in 593, having been deposed the year before, possibly by his successor, Ceol. He is recorded in various sources as having two sons, Cutha and Cuthwine, but the genealogies in which this information is found are known to be unreliable.

Historical context
The history of the sub-Roman period in Britain is poorly sourced and the subject of a number of important disagreements among historians. It appears, however, that in the fifth century, raids on Britain by continental peoples developed into migrations. The newcomers included Angles, Saxons, Jutes and Frisians. These peoples captured territory in the east and south of England, but at about the end of the fifth century, a British victory at the battle of Mons Badonicus halted the Anglo-Saxon advance for fifty years. Near the year 550, however, the British began to lose ground once more, and within twenty-five years, it appears that control of almost all of southern England was in the hands of the invaders.

The peace following the battle of Mons Badonicus is attested partly by Gildas, a monk, who wrote De Excidio et Conquestu Britanniae or On the Ruin and Conquest of Britain during the middle of the sixth century. This essay is a polemic against corruption and Gildas provides little in the way of names and dates. He appears, however, to state that peace had lasted from the year of his birth to the time he was writing. The Anglo-Saxon Chronicle is the other main source that bears on this period, in particular in an entry for the year 827 that records a list of the kings who bore the title "bretwalda", or "Britain-ruler". That list shows a gap in the early sixth century that matches Gildas's version of events.

Ceawlin's reign belongs to the period of Anglo-Saxon expansion at the end of the sixth century. Though there are many unanswered questions about the chronology and activities of the early West Saxon rulers, it is clear that Ceawlin was one of the key figures in the final Anglo-Saxon conquest of southern Britain.

Early West Saxon sources
The two main written sources for early West Saxon history are the Anglo-Saxon Chronicle and the West Saxon Genealogical Regnal List. The Chronicle is a set of annals which were compiled near the year 890, during the reign of King Alfred the Great of Wessex. They record earlier material for the older entries, which were assembled from earlier annals that no longer survive, as well as from saga material that might have been transmitted orally. The Chronicle dates the arrival of the future "West Saxons" in Britain to 495, when Cerdic and his son, Cynric, land at Cerdices ora, or Cerdic's shore. Almost twenty annals describing Cerdic's campaigns and those of his descendants appear interspersed through the next hundred years of entries in the Chronicle. Although these annals provide most of what is known about Ceawlin, the historicity of many of the entries is uncertain.

The West Saxon Genealogical Regnal List is a list of rulers of Wessex, including the lengths of their reigns. It survives in several forms, including as a preface to the [B] manuscript of the Chronicle. Like the Chronicle, the List was compiled in its present form during the reign of Alfred the Great, but an earlier version of the List was also one of the sources of the Chronicle itself. Both the list and the Chronicle are influenced by the desire of their writers to use a single line of descent to trace the lineage of the Kings of Wessex through Cerdic to Gewis, the legendary eponymous ancestor of the West Saxons, who is made to descend from Woden. The result served the political purposes of the scribe but is riddled with contradictions for historians.

The contradictions may be seen clearly by calculating dates by different methods from various sources. The first event in West Saxon history whose date can be regarded as reasonably certain is the baptism of Cynegils, which occurred in the late 630s, perhaps as late as 640. The Chronicle dates Cerdic's arrival to 495, but adding up the lengths of the reigns as given in the West Saxon Genealogical Regnal List leads to the conclusion that Cerdic's reign might have started in 532, a difference of 37 years. Neither 495 nor 532 may be treated as reliable; however, the latter date relies on the presumption that the Regnal List is correct in presenting the Kings of Wessex as having succeeded one another, with no omitted kings, and no joint kingships, and that the durations of the reigns are correct as given. None of these presumptions may be made safely.

The sources also are inconsistent on the length of Ceawlin's reign. The Chronicle gives it as thirty-two years, from 560 to 592, but the manuscripts of the Regnal List disagree: different copies give it as seven or seventeen years. David Dumville's detailed study of the Regnal List finds that it originally dated the arrival of the West Saxons in England to 532, and favours seven years as the earliest claimed length of Ceawlin's reign, with dates of 581–588 proposed. Dumville suggests that Ceawlin's reign length was then inflated to help extend the longevity of the Cerdicing dynasty further back into the past and that Ceawlin's reign specifically was extended because he is mentioned by Bede, giving him a status which led later West Saxon historians to conclude that he deserved a more impressive-looking reign. The sources do agree that Ceawlin is the son of Cynric and he usually is named as the father of Cuthwine. There is one discrepancy in this case: the entry for 685 in the [A] version of the Chronicle assigns Ceawlin a son, Cutha, but in the 855 entry in the same manuscript, Cutha is listed as the son of Cuthwine. Cutha also is named as Ceawlin's brother in the [E] and [F] versions of the Chronicle, in the 571 and 568 entries, respectively.

Whether Ceawlin is a descendant of Cerdic is a matter of debate. Subgroupings of different West Saxon lineages give the impression of separate groups, of which Ceawlin's line is one. Some of the problems in the Wessex genealogies may have come about because of efforts to integrate Ceawlin's line with the other lineages: it became very important to the West Saxons to be able to trace the ancestors of their rulers back to Cerdic. Another reason for doubting the literal nature of these early genealogies is that the etymology of the names of several early members of the dynasty does not appear to be Germanic, as would be expected in the names of leaders of an apparently Anglo-Saxon dynasty. The name Ceawlin has no convincing Old English etymology; it seems more likely to be of British origin.

The earliest sources do not use the term "West Saxon". According to Bede's Ecclesiastical History of the English People, the term is interchangeable with the Gewisse. The term "West Saxon" appears only in the late seventh century, after the reign of Cædwalla.

West Saxon expansion

Ultimately, the kingdom of Wessex occupied the southwest of England, but the initial stages in this expansion are not apparent from the sources. Cerdic's landing, whenever it is to be dated, seems to have been near the Isle of Wight, and the annals record the conquest of the island in 530. In 534, according to the Chronicle, Cerdic died and his son Cynric took the throne; the Chronicle adds that "they gave the Isle of Wight to their nephews, Stuf and Wihtgar". These records are in direct conflict with Bede, who states that the Isle of Wight was settled by Jutes, not Saxons; the archaeological record is somewhat in favour of Bede on this.

Subsequent entries in the Chronicle give details of some of the battles by which the West Saxons won their kingdom. Ceawlin's campaigns are not given as near the coast. They range along the Thames Valley and beyond, as far as Surrey in the east and the mouth of the Severn in the west. Ceawlin clearly is part of the West Saxon expansion, but the military history of the period is difficult to understand. In what follows the dates are as given in the Chronicle, although, as noted above, these are earlier than now thought accurate.

556: Beran byrg
The first record of a battle fought by Ceawlin is in 556, when he and his father, Cynric, fought the native Britons at "Beran byrg", or Bera's Stronghold. This now is identified as Barbury Castle, an Iron Age hill fort in Wiltshire, near Swindon. Cynric would have been king of Wessex at this time.

568: Wibbandun
The first battle Ceawlin fought as king is dated by the Chronicle to 568 when he and Cutha fought with Æthelberht, the king of Kent. The entry says "Here Ceawlin and Cutha fought against Aethelberht and drove him into Kent; and they killed two ealdormen, Oslaf and Cnebba, on Wibbandun." The location of "Wibbandun", which can be translated as "Wibba's Mount", has not been identified definitely; it was at one time thought to be Wimbledon, but this now is known to be incorrect.

David Cooper proposes Wyboston, a small village 8 miles north-east of Bedford on the west bank of the Great Ouse. Wibbandun is often written as Wibba's Dun, which is close phonetically to Wyboston and Æthelberht's dominance, from Kent to the Humber according to Bede, extended across those Anglian territories south of the Wash. It was this region that came under threat from Ceawlin as he looked to establish a defensible boundary on the Great Ouse River in the easternmost part of his territory. In addition, Cnebba, named as slain in this battle, has been associated with Knebworth, which lies 20 miles to the south of Wyboston. Half a mile south of Wyboston is a village called Chawston. The origin of the place name is unknown but might be derived from the Old English Ceawston or Ceawlinston. A defeat at Wyboston for Æthelberht would have damaged his overlord status and diminished his influence over the Anglians. The idea that he was driven or "pursued" into Kent (depending on which Anglo-Saxon Chronicle translation is preferred) should not be taken literally. Similar phraseology is often found in the Chronicle when one king bests another. A defeat suffered as part of an expedition to help his Anglian clients would have caused Æthelberht to withdraw into Kent to recover.

This battle is notable as the first recorded conflict between the invading peoples: previous battles recorded in the Chronicle are between the Anglo-Saxons and the native Britons.

There are multiple examples of joint kingship in Anglo-Saxon history, and this may be another: it is not clear what Cutha's relationship to Ceawlin is, but it certainly is possible he was also a king. The annal for 577, below, is another possible example.

571: Bedcanford
The annal for 571 reads: "Here Cuthwulf fought against the Britons at Bedcanford, and took four settlements: Limbury and Aylesbury, Benson and Eynsham; and in the same year he passed away." Cuthwulf's relationship with Ceawlin is unknown, but the alliteration common to Anglo-Saxon royal families suggests Cuthwulf may be part of the West Saxon royal line. The location of the battle itself is unidentified. It has been suggested that it was Bedford, but what is known of the early history of Bedford's names does not support this. This battle is of interest because it is surprising that an area so far east should still be in Briton hands this late: there is ample archaeological evidence of early Saxon and Anglian presence in the Midlands, and historians generally have interpreted Gildas's De Excidio as implying that the Britons had lost control of this area by the mid-sixth century. One possible explanation is that this annal records a reconquest of land that was lost to the Britons in the campaigns ending in the battle of Mons Badonicus.

577: Lower Severn
The annal for 577 reads "Here Cuthwine and Ceawlin fought against the Britons, and they killed three kings, Coinmail and Condidan and Farinmail, in the place which is called Dyrham, and took three cities: Gloucester and Cirencester and Bath." This entry is all that is known of these Briton kings; their names are in an archaic form that makes it very likely that this annal derives from a much older written source. The battle itself has long been regarded as a key moment in the Saxon advance, since in reaching the Bristol Channel, the West Saxons divided the Britons west of the Severn from land communication with those in the peninsula to the south of the Channel. Wessex almost certainly lost this territory to Penda of Mercia in 628, when the Chronicle records that "Cynegils and Cwichelm fought against Penda at Cirencester and then came to an agreement."

It is possible that when Ceawlin and Cuthwine took Bath, they found the Roman baths still operating to some extent. Nennius, a ninth-century historian, mentions a "Hot Lake" in the land of the Hwicce, which was along the Severn, and adds "It is surrounded by a wall, made of brick and stone, and men may go there to bathe at any time, and every man can have the kind of bath he likes. If he wants, it will be a cold bath; and if he wants a hot bath, it will be hot". Bede also describes hot baths in the geographical introduction to the Ecclesiastical History in terms very similar to those of Nennius.

Wansdyke, an early-medieval defensive linear earthwork, runs from south of Bristol to near Marlborough, Wiltshire, passing not far from Bath. It probably was built in the fifth or sixth centuries, perhaps by Ceawlin.

584: Fethan leag
Ceawlin's last recorded victory is in 584. The entry reads "Here Ceawlin and Cutha fought against the Britons at the place which is named Fethan leag, and Cutha was killed, and Ceawlin took many towns and countless war-loot, and in anger, he turned back to his own [territory]." There is a wood named "Fethelée" mentioned in a twelfth-century document that relates to Stoke Lyne, in Oxfordshire, and it now is thought that the battle of Fethan leag must have been fought in this area.

The phrase "in anger he turned back to his own" probably indicates that this annal is drawn from saga material, as perhaps are all of the early Wessex annals. It also has been used to argue that perhaps, Ceawlin did not win the battle and that the chronicler chose not to record the outcome fully—a king does not usually come home "in anger" after taking "many towns and countless war-loot". It may be that Ceawlin's overlordship of the southern Britons came to an end with this battle.

Bretwaldaship

About 731, Bede, a Northumbrian monk and chronicler, wrote a work called the Ecclesiastical History of the English People. The work was not primarily a secular history, but Bede provides much information about the history of the Anglo-Saxons, including a list early in the history of seven kings who, he said, held "imperium" over the other kingdoms south of the Humber. The usual translation for "imperium" is "overlordship". Bede names Ceawlin as the second on the list, although he spells it "Caelin", and adds that he was "known in the speech of his own people as Ceaulin". Bede also makes it clear that Ceawlin was not a Christian—Bede mentions a later king, Æthelberht of Kent, as "the first to enter the kingdom of heaven".

The Anglo-Saxon Chronicle, in an entry for the year 827, repeats Bede's list, adds Egbert of Wessex, and also mentions that they were known as "bretwalda", or "Britain-ruler". A great deal of scholarly attention has been given to the meaning of this word. It has been described as a term "of encomiastic poetry", but there also is evidence that it implied a definite role of military leadership.

Bede says that these kings had authority "south of the Humber", but the span of control, at least of the earlier bretwaldas, likely was less than this. In Ceawlin's case the range of control is hard to determine accurately, but Bede's inclusion of Ceawlin in the list of kings who held imperium, and the list of battles he is recorded as having won, indicates an energetic and successful leader who, from a base in the upper Thames valley, dominated much of the surrounding area and held overlordship over the southern Britons for some period. Despite Ceawlin's military successes, the northern conquests he made could not always be retained: Mercia took much of the upper Thames valley, and the north-eastern towns won in 571 were among territory subsequently under the control of Kent and Mercia at different times.

Bede's concept of the power of these overlords also must be regarded as the product of his eighth century viewpoint. When the Ecclesiastical History was written, Æthelbald of Mercia dominated the English south of the Humber, and Bede's view of the earlier kings was doubtless strongly coloured by the state of England at that time. For the earlier bretwaldas, such as Ælle and Ceawlin, there must be some element of anachronism in Bede's description. It also is possible that Bede only meant to refer to power over Anglo-Saxon kingdoms, not the native Britons.

Ceawlin is the second king on Bede's list. All the subsequent bretwaldas followed more or less consecutively, but there is a long gap, perhaps fifty years, between Ælle of Sussex, the first bretwalda, and Ceawlin. The lack of gaps between the overlordships of the later bretwaldas has been used to make an argument for Ceawlin's dates matching the later entries in the Chronicle with reasonable accuracy. According to this analysis, the next bretwalda, Æthelberht of Kent, must have been already a dominant king by the time Pope Gregory the Great wrote to him in 601, since Gregory would have not written to an underking. Ceawlin defeated Æthelberht in 568 according to the Chronicle. Æthelberht's dates are a matter of debate, but recent scholarly consensus has his reign starting no earlier than 580. The 568 date for the battle at Wibbandun is thought to be unlikely because of the assertion in various versions of the West Saxon Genealogical Regnal List that Ceawlin's reign lasted either seven or seventeen years. If this battle is placed near the year 590, before Æthelberht had established himself as a powerful king, then the subsequent annals relating to Ceawlin's defeat and death may be reasonably close to the correct date. In any case, the battle with Æthelberht is unlikely to have been more than a few years on either side of 590. The gap between Ælle and Ceawlin, on the other hand, has been taken as supporting evidence for the story told by Gildas in De Excidio of a peace lasting a generation or more following a Briton victory at Mons Badonicus.

Æthelberht of Kent succeeds Ceawlin on the list of bretwaldas, but the reigns may overlap somewhat: recent evaluations give Ceawlin a likely reign of 581–588, and place Æthelberht's accession near to the year 589, but these analyses are no more than scholarly guesses. Ceawlin's eclipse in 592, probably by Ceol, may have been the occasion for Æthelberht to rise to prominence; Æthelberht very likely was the dominant Anglo-Saxon king by 597. Æthelberht's rise may have been earlier: the 584 annal, even if it records a victory, is the last victory of Ceawlin's in the Chronicle, and the period after that may have been one of Æthelberht's ascent and Ceawlin's decline.

Wessex at Ceawlin's death

Ceawlin lost the throne of Wessex in 592. The annal for that year reads, in part: "Here there was great slaughter at Woden's Barrow, and Ceawlin was driven out." Woden's Barrow is a tumulus, now called Adam's Grave, at Alton Priors, Wiltshire. No details of his opponent are given. The medieval chronicler William of Malmesbury, writing in about 1120, says that it was "the Angles and the British conspiring together". Alternatively, it may have been Ceol, who is supposed to have been the next king of Wessex, ruling for six years according to the West Saxon Genealogical Regnal List. According to the Anglo-Saxon Chronicle, Ceawlin died the following year. The relevant part of the annal reads: "Here Ceawlin and Cwichelm and Crida perished." Nothing more is known of Cwichelm and Crida, although they may have been members of the Wessex royal house—their names fit the alliterative pattern common to royal houses of the time.

According to the Regnal List, Ceol was a son of Cutha, who was a son of Cynric; and Ceolwulf, his brother, reigned for seventeen years after him. It is possible that some fragmentation of control among the West Saxons occurred at Ceawlin's death: Ceol and Ceolwulf may have been based in Wiltshire, as opposed to the upper Thames valley. This split also may have contributed to Æthelberht's ability to rise to dominance in southern England. The West Saxons remained influential in military terms, however: the Chronicle and Bede record continued military activity against Essex and Sussex within twenty or thirty years of Ceawlin's death.

title: Ceawlin of Wessex


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Christchurch (disambiguation)

Christchurch is the largest city in the South Island of New Zealand.

Christchurch may also refer to:

New Zealand

 * Christchurch, New Zealand
 * Christchurch (New Zealand electorate), a former electorate in New Zealand, also called Town (or City) of Christchurch
 * Christchurch Central, the current electorate of Christchurch in New Zealand
 * Christchurch mosque shootings, a 2019 terrorist attack in Christchurch, New Zealand

United Kingdom

 * Christchurch, Cambridgeshire, in England
 * Christchurch, Dorset, town on the south coast of England
 * RAF Christchurch, a WW II airfield near the town
 * Christchurch (UK Parliament constituency), England, centred on the town
 * Christchurch (Dorset) railway station, a railway station serving the town
 * Christchurch, Gloucestershire, hamlet in the west of the Forest of Dean, Gloucestershire, England
 * Christchurch, Newport, in Wales
 * Christchurch Mansion, a stately home in Ipswich, Suffolk
 * Christchurch Park, a park surrounding Christchurch Mansion
 * Southwark Christchurch, England

Other countries

 * Christchurch, Virginia, United States
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Educational institutions

 * Canterbury Christ Church University
 * Christchurch School, Christchurch, Virginia, U.S.
 * Christchurch Boys' High School, Christchurch, New Zealand
 * Christchurch Girls' High School, Christchurch, New Zealand
 * Christ Church, Oxford
 * University of Otago Christchurch School of Medicine, one of three medical schools of University of Otago, New Zealand
 * Christchurch Anglo-Indian Higher Secondary School, Christchurch, Chennai, India

Sports teams

 * Christchurch F.C., England
 * Christchurch United, New Zealand
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Other uses

 * Christchurch-Campbell, an automobile made in 1922
 * ChristChurch London, an evangelic church in London, England
 * Christchurch, Ilkley, a church in West Yorkshire, England

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

title: Christchurch (disambiguation)


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CD-R

CD-R (Compact disc-recordable) is a digital optical disc storage format. A CD-R disc is a compact disc that can only be written once and read arbitrarily many times.

CD-R discs (CD-Rs) are readable by most CD readers manufactured prior to the introduction of CD-R, unlike CD-RW discs.

History
Originally named CD Write-Once (WO), the CD-R specification was first published in 1988 by Philips and Sony in the Orange Book, which consists of several parts that provide details of the CD-WO, CD-MO (Magneto-Optic), and later CD-RW (Re Writable). The latest editions have abandoned the use of the term CD-WO in favor of CD-R, while CD-MO was rarely used. Written CD-Rs and CD-RWs are, in the aspect of low-level encoding and data format, fully compatible with the audio CD (Red Book CD-DA) and data CD (Yellow Book CD-ROM) standards. The Yellow Book standard for CD-ROM only specifies a high-level data format and refers to the Red Book for all physical format and low-level code details, such as track pitch, linear bit density, and bitstream encoding. This means they use Eight-to-Fourteen Modulation, CIRC error correction, and, for CD-ROM, the third error correction layer defined in the Yellow Book. Properly written CD-R discs on blanks of less than 80 minutes in length are fully compatible with the audio CD and CD-ROM standards in all details including physical specifications. 80-minute CD-R discs marginally violate the Red Book physical format specifications, and longer discs are non-compliant. CD-RW discs have lower reflectivity than CD-R or pressed (non-writable) CDs and for this reason cannot meet the Red Book standard. Some hardware compatible with Red Book CDs may have difficulty reading CD-Rs and, because of their lower reflectivity, especially CD-RWs. To the extent that CD hardware can read extended-length discs or CD-RW discs, it is because that hardware has capability beyond the minimum required by the Red Book and Yellow Book standards (the hardware is more capable than it needs to be to bear the Compact Disc logo).

CD-R recording systems available in 1990 were similar to the washing machine-sized Meridian CD Publisher, based on the two-piece rack mount Yamaha PDS audio recorder costing $35,000, not including the required external ECC circuitry for data encoding, SCSI hard drive subsystem, and MS-DOS control computer.

On July 3, 1991, the first recording of a concert directly to CD was made using a Yamaha YPDR 601. The concert was performed by Claudio Baglioni at the Stadio Flaminio in Rome, Italy. At that time, it was generally anticipated that recordable CDs would have a lifetime of no more than 10 years. However, as of July 2020 the CD from this live recording still plays back with no uncorrectable errors.

In the same year, the first company to successfully & professionally duplicate CD-R media was CDRM Recordable Media. With quality technical media being limited from Taiyo Yuden, Early CD-R Media used Phthalocyanine dye for duplication, which has a light aqua color. By 1992, the cost of typical recorders was down to $10,000–12,000, and in September 1995, Hewlett-Packard introduced its model 4020i manufactured by Philips, which, at $995, was the first recorder to cost less than $1000. As of the 2010s, devices capable of writing to CD-Rs and other types of writable CDs could be found under $20.

The dye materials developed by Taiyo Yuden made it possible for CD-R discs to be compatible with Audio CD and CD-ROM discs.

In the United States, there is a market separation between "music" CD-Rs and "data" CD-Rs, the former being notably more expensive than the latter due to industry copyright arrangements with the RIAA. Specifically, the price of every music CD-R includes a mandatory royalty disbursed to RIAA members by the disc manufacturer; this grants the disc an "application flag" indicating that the royalty has been paid. Consumer standalone music recorders refuse to burn CD-Rs that are missing this flag. Professional CD recorders are not subject to this restriction and can record music to data discs. The two types of discs are functionally and physically identical other than this, and computer CD burners can record data and/or music to either. New music CD-Rs are still being manufactured as of the late 2010s, although demand for them has declined as CD-based music recorders have been supplanted by other devices incorporating the same or similar functionality.

Prior to CD-R, Tandy Corporation had announced a rewritable CD system known as the Tandy High-Density Optical Recording (THOR) system, claiming to offer support for erasable and rewritable discs, made possible by a "secret coating material" on which Tandy had applied for patents, and reportedly based partly on a process developed by Optical Data Inc., with research and development undertaken at Tandy's Magnetic Media Research Center. Known also as the Tandy High-Intensity Optical Recording system, THOR-CD media was intended to be playable in existing CD players, being compatible with existing CD audio and CD-ROM equipment, with the discs themselves employing a layer in which the "marks", "bumps" or "pits" readable by a conventional CD player could be established in, and removed from, the medium by a laser operating at a different frequency. Tandy's announcement was surprising enough to "catch half a dozen industries off guard", claiming availability of consumer-level audio and video products below $500 by the end of 1990, and inviting other organisations to license the technology. The announcement attracted enthusiasm but also skepticism of Tandy's capability to deliver the system, with the latter proving to be justified, the technology having been "announced... heavily promoted; then it was delayed, and finally, it just never appeared".

Physical characteristics

A standard CD-R is a 1.2 mm thick disc made of polycarbonate about 120 mm (5") in diameter. The 120 mm (5") disc has a storage capacity of 74 minutes of audio or 650 Megabytes (MBs) of data. CD-R/RWs are available with capacities of 80 minutes of audio or 737,280,000 bytes (700 MB), which they achieve by molding the disc at the tightest allowable tolerances specified in the Orange Book CD-R/CD-RW standards. The engineering margin that was reserved for manufacturing tolerance has been used for data capacity instead, leaving no tolerance for manufacturing; for these discs to be truly compliant with the Orange Book standard, the manufacturing process must be perfect.

Despite the foregoing, most CD-Rs on the market have an 80-minute capacity. There are also 90 minute/790 MB and 99 minute/870 MB discs, although they are less common and depart from the Orange Book standard. Due to the limitations of the data structures in the ATIP, 90 and 99-minute blanks will identify as 80-minute ones. As the ATIP is part of the Orange Book standard, its design does not support some nonstandard disc configurations. In order to use the additional capacity, these discs have to be burned using overburn options in the CD recording software. Overburning itself is so named because it is outside the written standards, but, due to market demand, it has nonetheless become a de facto standard function in most CD writing drives and software for them.

Some drives use special techniques, such as Plextor's GigaRec or Sanyo's HD-BURN, to write more data onto a given disc; these techniques are deviations from the compact disc (Red, Yellow, and/or Orange Book) standards, making the recorded discs proprietary-formatted and not fully compatible with standard CD players and drives. In certain applications where discs will not be distributed or exchanged outside a private group and will not be archived for a long time, a proprietary format may be an acceptable way to obtain greater capacity (up to 1.2 GB with GigaRec or 1.8 GB with HD-BURN on 99-minute media). The greatest risk in using such a proprietary data storage format, assuming that it works reliably as designed, is that it may be difficult or impossible to repair or replace the hardware used to read the media if it fails, is damaged, or is lost after its original vendor discontinues it.

Nothing in the Red, Yellow, or Orange Book standards prohibits disc reading/writing devices from having the capacity to read/write discs beyond the compact disc standards. The standards do require discs to meet precise requirements in order to be called compact discs, but the other discs may be called by other names; if this were not true, no DVD drive could legally bear the compact disc logo. While disc players and drives may have capabilities beyond the standards, enabling them to read and write nonstandard discs, there is no assurance, in the absence of explicit additional manufacturer specifications beyond normal compact disc logo certification, that any particular player or drive will perform beyond the standards at all or consistently. If the same device with no explicit performance specs beyond the compact disc logo initially handles nonstandard discs reliably, there is no assurance that it will not later stop doing so, and in that case, there is no assurance that it can be made to do so again by service or adjustment. Discs with capacities larger than 650 MB, and especially those larger than 700 MB, are less interchangeable among players/drives than standard discs and are not very suitable for archival use, as their readability on future equipment, or even on the same equipment at a future time, is not assured unless specifically tested and certified in that combination, even under the assumption that the discs will not degrade at all.

The polycarbonate disc contains a spiral groove, called the pregroove because it is molded in before data are written to the disc; it guides the laser beam upon writing and reading information. The pregroove is molded into the top side of the polycarbonate disc, where the pits and lands would be molded if it were a pressed, nonrecordable Red Book CD. The bottom side, which faces the laser beam in the player or drive, is flat and smooth. The polycarbonate disc is coated on the pregroove side with a very thin layer of organic dye. Then, on top of the dye is coated a thin, reflecting layer of silver, a silver alloy, or gold. Finally, a protective coating of a photo-polymerizable lacquer is applied on top of the metal reflector and cured with UV light.

A blank CD-R is not "empty"; the pregroove has a wobble (the ATIP), which helps the writing laser to stay on track and to write the data to the disc at a constant rate. Maintaining a constant rate is essential to ensure the proper size and spacing of the pits and lands burned into the dye layer. As well as providing timing information, the ATIP (absolute time in pregroove) is also a data track containing information about the CD-R manufacturer, the dye used, and media information (disc length and so on). The pregroove is not destroyed when the data are written to the CD-R, a point which some copy protection schemes use to distinguish copies from an original CD.

Dyes
There are three basic formulations of dye used in CD-Rs:
 * 1) Cyanine dye CD-Rs were the earliest ones developed, and their formulation is patented by Taiyo Yuden. CD-Rs based on this dye are mostly green in color. The earlier models were very chemically unstable and this made cyanine-based discs unsuitable for archival use; they could fade and become unreadable in a few years. Many manufacturers like Taiyo Yuden use proprietary chemical additives, typically a metal atom bonded to the cyanine molecule, to make more stable cyanine discs ("metal-stabilized Cyanine", "Super Cyanine"). Older cyanine dye-based CD-Rs, as well as all the hybrid dyes based on cyanine, are very sensitive to UV-rays and can become unreadable after only a few days if they were exposed to direct sunlight. Although the additives used have made cyanine more stable, it is still the most sensitive of the dyes in UV rays (showing signs of degradation within a week of direct sunlight exposure). A common mistake users make is to leave the CD-Rs with the "clear" (recording) surface upwards, in order to protect it from scratches, as this lets the sun hit the recording surface directly.
 * 2) Phthalocyanine dye CD-Rs are usually silver, gold, or light green. The patents on phthalocyanine CD-Rs are held by Mitsui and Ciba Specialty Chemicals. Phthalocyanine is a natively stable dye (has no need for stabilizers) and CD-Rs based on this are often given a rated lifetime of hundreds of years. Unlike cyanine, phthalocyanine is more resistant to UV rays, and CD-Rs based on this dye show signs of degradation only after two weeks of direct sunlight exposure. However, phthalocyanine is more sensitive than cyanine to writing laser power calibration, meaning that the power level used by the writing laser has to be more accurately adjusted for the disc in order to get a good recording; this may erode the benefits of dye stability, as marginally written discs (with higher correctable error rates) will lose data (i.e. have uncorrectable errors) after less dye degradation than well-written discs (with lower correctable error rates).
 * 3) Azo dye CD-Rs are dark blue in color, and their formulation is patented by Mitsubishi Chemical Corporation. Azo dyes are also chemically stable, and Azo CD-Rs are typically rated with a lifetime of decades. Azo is the most resistant dye against UV light and begins to degrade only after the third or fourth week of direct sunlight exposure. More modern implementations of this kind of dye include Super Azo which is not as deep blue as the earlier Metal Azo. This change of composition was necessary in order to achieve higher writing speeds.

There are many hybrid variations of the dye formulations, such as Formazan by Kodak (a hybrid of cyanine and phthalocyanine).

Many manufacturers have added additional coloring to disguise their unstable cyanine CD-Rs in the past, so the formulation of a disc cannot be determined based purely on its color. Similarly, a gold reflective layer does not guarantee the use of phthalocyanine dye. The quality of the disc is also not only dependent on the dye used, it is also influenced by sealing, the top layer, the reflective layer, and the polycarbonate. Simply choosing a disc based on its dye type may be problematic. Furthermore, correct power calibration of the laser in the writer, as well as correct timing of the laser pulses, stable disc speed, and so on, is critical to not only the immediate readability but the longevity of the recorded disc, so for archiving it is important to have not only a high-quality disc but a high-quality writer. In fact, a high-quality writer may produce adequate results with medium-quality media, but high-quality media cannot compensate for a mediocre writer, and discs written by such a writer cannot achieve their maximum potential archival lifetime.

Speed
These times only include the actual optical writing pass over the disc. For most disc recording operations, additional time is used for overhead processes, such as organizing the files and tracks, which adds to the theoretical minimum total time required to produce a disc. (An exception might be making a disc from a prepared ISO image, for which the overhead would likely be trivial.) At the lowest write speeds, this overhead takes so much less time than the actual disc writing pass that it may be negligible, but at higher write speeds, the overhead time becomes a larger proportion of the overall time taken to produce a finished disc and may add significantly to it.

Also, above 20× speed, drives use a Zoned-CLV or CAV strategy, where the advertised maximum speed is only reached near the outer rim of the disc. This is not taken into account by the above table. (If this were not done, the faster rotation that would be required at the inner tracks could cause the disc to fracture and/or could cause excessive vibration which would make accurate and successful writing impossible.)

Writing methods
The blank disc has a pre-groove track onto which the data are written. The pre-groove track, which also contains timing information, ensures that the recorder follows the same spiral path as a conventional CD. A CD recorder writes data to a CD-R disc by pulsing its laser to heat areas of the organic dye layer. The writing process does not produce indentations (pits); instead, the heat permanently changes the optical properties of the dye, changing the reflectivity of those areas. Using a low power laser, so as not to further alter the dye, the disc is read back in the same way as a CD-ROM. However, the reflected light is modulated not by pits, but by the alternating regions of heated and unaltered dye. The change of the intensity of the reflected laser radiation is transformed into an electrical signal, from which the digital information is recovered ("decoded"). Once a section of a CD-R is written, it cannot be erased or rewritten, unlike a CD-RW. A CD-R can be recorded in multiple sessions. A CD recorder can write to a CD-R using several methods including:
 * 1) Disc At Once – the whole CD-R is written in one session with no gaps and the disc is "closed" meaning no more data can be added and the CD-R effectively becomes a standard read-only CD. With no gaps between the tracks, the Disc At Once format is useful for "live" audio recordings.
 * 2) Track At Once – data are written to the CD-R one track at a time but the CD is left "open" for further recording at a later stage. It also allows data and audio to reside on the same CD-R.
 * 3) Packet Writing – used to record data to a CD-R in "packets", allowing extra information to be appended to a disc at a later time, or for information on the disc to be made "invisible". In this way, CD-R can emulate CD-RW; however, each time information on the disc is altered, more data has to be written to the disc. There can be compatibility issues with this format and some CD drives.

With careful examination, the written and unwritten areas can be distinguished by the naked eye. CD-Rs are written from the center outwards, so the written area appears as an inner band with slightly different shading.

CDs have a Power Calibration Area, used to calibrate the writing laser before and during recording. CDs contain two such areas: one close to the inner edge of the disc, for low-speed calibration, and another on the outer edge on the disc, for high-speed calibration. The calibration results are recorded on a Recording Management Area (RMA) that can hold up to 99 calibrations. The disc cannot be written after the RMA is full, however, the RMA may be emptied in CD-RW discs.

Lifespan
Real-life (not accelerated aging) tests have revealed that some CD-Rs degrade quickly even if stored normally. The quality of a CD-R disc has a large and direct influence on longevity—low-quality discs should not be expected to last very long. According to research conducted by J. Perdereau, CD-Rs are expected to have an average life expectancy of 10 years. Branding is not a reliable guide to quality, because many brands (major as well as no name) do not manufacture their own discs. Instead, they are sourced from different manufacturers of varying quality. For best results, the actual manufacturer and material components of each batch of discs should be verified.

Burned CD-Rs suffer from material degradation, just like most writable media. CD-R media have an internal layer of dye used to store data. In a CD-RW disc, the recording layer is made of an alloy of silver and other metals—indium, antimony, and tellurium. In CD-R media, the dye itself can degrade, causing data to become unreadable.

As well as degradation of the dye, failure of a CD-R can be due to the reflective surface. While silver is less expensive and more widely used, it is more prone to oxidation, resulting in a non-reflecting surface. Gold, on the other hand, although more expensive and no longer widely used, is an inert material, so gold-based CD-Rs do not suffer from this problem. Manufacturers have estimated the longevity of gold-based CD-Rs to be as high as 100 years.

By measuring the rate of correctable data errors, the data integrity and/or manufacturing quality of CD-R media can be measured, allowing for a reliable prediction of future data losses caused by media degradation.

Labeling
It is recommended if using adhesive-backed paper labels that the labels be specially made for CD-Rs. A balanced CD vibrates only slightly when rotated at high speed. Bad or improperly made labels, or labels applied off-center, unbalance the CD and can cause it to vibrate when it spins, which causes read errors and even risks damaging the drive. A professional alternative to CD labels is pre-printed CDs using a 5-color silkscreen or offset press. Using a permanent marker pen is also a common practice. However, solvents from such pens can affect the dye layer.

Data confidentiality
Since CD-Rs, in general, cannot be logically erased to any degree, the disposal of CD-Rs presents a possible security issue if they contain sensitive/private data. Destroying the data requires physically destroying the disc or data layer. Heating the disc in a microwave oven for 10–15 seconds effectively destroys the data layer by causing arcing in the metal reflective layer, but this same arcing may cause damage or excessive wear to the microwave oven. Many office paper shredders are also designed to shred CDs.

Some recent burners (Plextor, LiteOn) support erase operations on -R media, by "overwriting" the stored data with strong laser power, although the erased area cannot be overwritten with new data.

Recycling
The polycarbonate material and possible gold or silver in the reflective layer would make CD-Rs highly recyclable. However, the polycarbonate is of very little value and the quantity of precious metals is so small that it is not profitable to recover them. Consequently, recyclers that accept CD-Rs typically do not offer compensation for donating or transporting the materials.

title: CD-R


text:
Cytosol

The cytosol, also known as cytoplasmic matrix or groundplasm, is one of the liquids found inside cells (intracellular fluid (ICF)). It is separated into compartments by membranes. For example, the mitochondrial matrix separates the mitochondrion into many compartments.

In the eukaryotic cell, the cytosol is surrounded by the cell membrane and is part of the cytoplasm, which also comprises the mitochondria, plastids, and other organelles (but not their internal fluids and structures); the cell nucleus is separate. The cytosol is thus a liquid matrix around the organelles. In prokaryotes, most of the chemical reactions of metabolism take place in the cytosol, while a few take place in membranes or in the periplasmic space. In eukaryotes, while many metabolic pathways still occur in the cytosol, others take place within organelles.

The cytosol is a complex mixture of substances dissolved in water. Although water forms the large majority of the cytosol, its structure and properties within cells is not well understood. The concentrations of ions such as sodium and potassium in the cytosol are different to those in the extracellular fluid; these differences in ion levels are important in processes such as osmoregulation, cell signaling, and the generation of action potentials in excitable cells such as endocrine, nerve and muscle cells. The cytosol also contains large amounts of macromolecules, which can alter how molecules behave, through macromolecular crowding.

Although it was once thought to be a simple solution of molecules, the cytosol has multiple levels of organization. These include concentration gradients of small molecules such as calcium, large complexes of enzymes that act together and take part in metabolic pathways, and protein complexes such as proteasomes and carboxysomes that enclose and separate parts of the cytosol.

Definition
The term "cytosol" was first introduced in 1965 by H. A. Lardy, and initially referred to the liquid that was produced by breaking cells apart and pelleting all the insoluble components by ultracentrifugation. Such a soluble cell extract is not identical to the soluble part of the cell cytoplasm and is usually called a cytoplasmic fraction.

The term cytosol is now used to refer to the liquid phase of the cytoplasm in an intact cell. This excludes any part of the cytoplasm that is contained within organelles. Due to the possibility of confusion between the use of the word "cytosol" to refer to both extracts of cells and the soluble part of the cytoplasm in intact cells, the phrase "aqueous cytoplasm" has been used to describe the liquid contents of the cytoplasm of living cells.

Prior to this, other terms, including hyaloplasm, were used for the cell fluid, not always synonymously, as its nature was not well understood (see protoplasm).

Properties and composition
The proportion of cell volume that is cytosol varies: for example while this compartment forms the bulk of cell structure in bacteria, in plant cells the main compartment is the large central vacuole. The cytosol consists mostly of water, dissolved ions, small molecules, and large water-soluble molecules (such as proteins). The majority of these non-protein molecules have a molecular mass of less than 300 Da. This mixture of small molecules is extraordinarily complex, as the variety of molecules that are involved in metabolism (the metabolites) is immense. For example, up to 200,000 different small molecules might be made in plants, although not all these will be present in the same species, or in a single cell. Estimates of the number of metabolites in single cells such as E. coli and baker's yeast predict that under 1,000 are made.

Water
Most of the cytosol is water, which makes up about 70% of the total volume of a typical cell. The pH of the intracellular fluid is 7.4. while human cytosolic pH ranges between 7.0–7.4, and is usually higher if a cell is growing. The viscosity of cytoplasm is roughly the same as pure water, although diffusion of small molecules through this liquid is about fourfold slower than in pure water, due mostly to collisions with the large numbers of macromolecules in the cytosol. Studies in the brine shrimp have examined how water affects cell functions; these saw that a 20% reduction in the amount of water in a cell inhibits metabolism, with metabolism decreasing progressively as the cell dries out and all metabolic activity halting when the water level reaches 70% below normal.

Although water is vital for life, the structure of this water in the cytosol is not well understood, mostly because methods such as nuclear magnetic resonance spectroscopy only give information on the average structure of water, and cannot measure local variations at the microscopic scale. Even the structure of pure water is poorly understood, due to the ability of water to form structures such as water clusters through hydrogen bonds.

The classic view of water in cells is that about 5% of this water is strongly bound in by solutes or macromolecules as water of solvation, while the majority has the same structure as pure water. This water of solvation is not active in osmosis and may have different solvent properties, so that some dissolved molecules are excluded, while others become concentrated. However, others argue that the effects of the high concentrations of macromolecules in cells extend throughout the cytosol and that water in cells behaves very differently from the water in dilute solutions. These ideas include the proposal that cells contain zones of low and high-density water, which could have widespread effects on the structures and functions of the other parts of the cell. However, the use of advanced nuclear magnetic resonance methods to directly measure the mobility of water in living cells contradicts this idea, as it suggests that 85% of cell water acts like that pure water, while the remainder is less mobile and probably bound to macromolecules.

Ions
The concentrations of the other ions in cytosol are quite different from those in extracellular fluid and the cytosol also contains much higher amounts of charged macromolecules such as proteins and nucleic acids than the outside of the cell structure.

In contrast to extracellular fluid, cytosol has a high concentration of potassium ions and a low concentration of sodium ions. This difference in ion concentrations is critical for osmoregulation, since if the ion levels were the same inside a cell as outside, water would enter constantly by osmosis - since the levels of macromolecules inside cells are higher than their levels outside. Instead, sodium ions are expelled and potassium ions taken up by the Na⁺/K⁺-ATPase, potassium ions then flow down their concentration gradient through potassium-selection ion channels, this loss of positive charge creates a negative membrane potential. To balance this potential difference, negative chloride ions also exit the cell, through selective chloride channels. The loss of sodium and chloride ions compensates for the osmotic effect of the higher concentration of organic molecules inside the cell.

Cells can deal with even larger osmotic changes by accumulating osmoprotectants such as betaines or trehalose in their cytosol. Some of these molecules can allow cells to survive being completely dried out and allow an organism to enter a state of suspended animation called cryptobiosis. In this state the cytosol and osmoprotectants become a glass-like solid that helps stabilize proteins and cell membranes from the damaging effects of desiccation.

The low concentration of calcium in the cytosol allows calcium ions to function as a second messenger in calcium signaling. Here, a signal such as a hormone or an action potential opens calcium channel so that calcium floods into the cytosol. This sudden increase in cytosolic calcium activates other signalling molecules, such as calmodulin and protein kinase C. Other ions such as chloride and potassium may also have signaling functions in the cytosol, but these are not well understood.

Macromolecules
Protein molecules that do not bind to cell membranes or the cytoskeleton are dissolved in the cytosol. The amount of protein in cells is extremely high, and approaches 200 mg/ml, occupying about 20–30% of the volume of the cytosol. However, measuring precisely how much protein is dissolved in cytosol in intact cells is difficult, since some proteins appear to be weakly associated with membranes or organelles in whole cells and are released into solution upon cell lysis. Indeed, in experiments where the plasma membrane of cells were carefully disrupted using saponin, without damaging the other cell membranes, only about one quarter of cell protein was released. These cells were also able to synthesize proteins if given ATP and amino acids, implying that many of the enzymes in cytosol are bound to the cytoskeleton. However, the idea that the majority of the proteins in cells are tightly bound in a network called the microtrabecular lattice is now seen as unlikely.

In prokaryotes the cytosol contains the cell's genome, within a structure known as a nucleoid. This is an irregular mass of DNA and associated proteins that control the transcription and replication of the bacterial chromosome and plasmids. In eukaryotes the genome is held within the cell nucleus, which is separated from the cytosol by nuclear pores that block the free diffusion of any molecule larger than about 10 nanometres in diameter.

This high concentration of macromolecules in cytosol causes an effect called macromolecular crowding, which is when the effective concentration of other macromolecules is increased, since they have less volume to move in. This crowding effect can produce large changes in both the rates and the position of chemical equilibrium of reactions in the cytosol. It is particularly important in its ability to alter dissociation constants by favoring the association of macromolecules, such as when multiple proteins come together to form protein complexes, or when DNA-binding proteins bind to their targets in the genome.

Organization
Although the components of the cytosol are not separated into regions by cell membranes, these components do not always mix randomly and several levels of organization can localize specific molecules to defined sites within the cytosol.

Concentration gradients
Although small molecules diffuse rapidly in the cytosol, concentration gradients can still be produced within this compartment. A well-studied example of these are the "calcium sparks" that are produced for a short period in the region around an open calcium channel. These are about 2 micrometres in diameter and last for only a few milliseconds, although several sparks can merge to form larger gradients, called "calcium waves". Concentration gradients of other small molecules, such as oxygen and adenosine triphosphate may be produced in cells around clusters of mitochondria, although these are less well understood.

Protein complexes
Proteins can associate to form protein complexes, these often contain a set of proteins with similar functions, such as enzymes that carry out several steps in the same metabolic pathway. This organization can allow substrate channeling, which is when the product of one enzyme is passed directly to the next enzyme in a pathway without being released into solution. Channeling can make a pathway more rapid and efficient than it would be if the enzymes were randomly distributed in the cytosol, and can also prevent the release of unstable reaction intermediates. Although a wide variety of metabolic pathways involve enzymes that are tightly bound to each other, others may involve more loosely associated complexes that are very difficult to study outside the cell. Consequently, the importance of these complexes for metabolism in general remains unclear.

Protein compartments
Some protein complexes contain a large central cavity that is isolated from the remainder of the cytosol. One example of such an enclosed compartment is the proteasome. Here, a set of subunits form a hollow barrel containing proteases that degrade cytosolic proteins. Since these would be damaging if they mixed freely with the remainder of the cytosol, the barrel is capped by a set of regulatory proteins that recognize proteins with a signal directing them for degradation (a ubiquitin tag) and feed them into the proteolytic cavity.

Another large class of protein compartments are bacterial microcompartments, which are made of a protein shell that encapsulates various enzymes. These compartments are typically about 100–200 nanometres across and made of interlocking proteins. A well-understood example is the carboxysome, which contains enzymes involved in carbon fixation such as RuBisCO.

Biomolecular condensates
Non-membrane bound organelles can form as biomolecular condensates, which arise by clustering, oligomerisation, or polymerisation of macromolecules to drive colloidal phase separation of the cytoplasm or nucleus.

Cytoskeletal sieving
Although the cytoskeleton is not part of the cytosol, the presence of this network of filaments restricts the diffusion of large particles in the cell. For example, in several studies tracer particles larger than about 25 nanometres (about the size of a ribosome) were excluded from parts of the cytosol around the edges of the cell and next to the nucleus. These "excluding compartments" may contain a much denser meshwork of actin fibres than the remainder of the cytosol. These microdomains could influence the distribution of large structures such as ribosomes and organelles within the cytosol by excluding them from some areas and concentrating them in others.

Function
The cytosol is the site of multiple cell processes. Examples of these processes include signal transduction from the cell membrane to sites within the cell, such as the cell nucleus, or organelles. This compartment is also the site of many of the processes of cytokinesis, after the breakdown of the nuclear membrane in mitosis. Another major function of cytosol is to transport metabolites from their site of production to where they are used. This is relatively simple for water-soluble molecules, such as amino acids, which can diffuse rapidly through the cytosol. However, hydrophobic molecules, such as fatty acids or sterols, can be transported through the cytosol by specific binding proteins, which shuttle these molecules between cell membranes. Molecules taken into the cell by endocytosis or on their way to be secreted can also be transported through the cytosol inside vesicles, which are small spheres of lipids that are moved along the cytoskeleton by motor proteins.

The cytosol is the site of most metabolism in prokaryotes, and a large proportion of the metabolism of eukaryotes. For instance, in mammals about half of the proteins in the cell are localized to the cytosol. The most complete data are available in yeast, where metabolic reconstructions indicate that the majority of both metabolic processes and metabolites occur in the cytosol. Major metabolic pathways that occur in the cytosol in animals are protein biosynthesis, the pentose phosphate pathway, glycolysis and gluconeogenesis. The localization of pathways can be different in other organisms, for instance fatty acid synthesis occurs in chloroplasts in plants and in apicoplasts in apicomplexa.

title: Cytosol


text:
Compound

Compound may refer to:

Architecture and built environments

 * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall
 * Compound (fortification), a version of the above fortified with defensive structures
 * Compound (migrant labour), a hostel for migrant workers such as those historically connected with mines in South Africa
 * The Compound, an area of Palm Bay, Florida, US
 * Komboni or compound, a type of slum in Zambia

Government and law

 * Composition (fine), a legal procedure in use after the English Civil War
 * Committee for Compounding with Delinquents, an English Civil War institution that allowed Parliament to compound the estates of Royalists
 * Compounding treason, an offence under the common law of England
 * Compounding a felony, a previous offense under the common law of England

Linguistics

 * Compound (linguistics), a word that consists of more than one radical element
 * Compound sentence (linguistics), a type of sentence made up of two or more independent clauses and no subordinate (dependent) clauses

Biology and medicine

 * Compounding, the mixing of drugs in pharmacy
 * Compound fracture, a complete fractures of bone where at least one fragment has damaged the skin, soft tissue or surrounding body cavity
 * Compound leaf, a type of leaf being divided into smaller leaflets

Chemistry and materials science

 * Chemical compound, combination of two or more elements
 * Plastic compounding, a method of preparing plastic formulations

Vehicles and engines

 * Compound engine, a steam engine in which steam is expanded through a series of two or three cylinders before exhaust
 * Turbo-compound engine, an internal combustion engine where exhaust gases expand through power-turbines
 * Compounding pressure, a method in which pressure in a steam turbine is made to drop in a number of stages

Other uses in science, technology, and mathematics

 * Compound bow, a type of bow for archery
 * Polyhedral compound, a polyhedron composed of multiple polyhedra sharing the same centre

Common names

 * Compound (music), an attribute of a time signature
 * Compound interest, in finance, unpaid interest that is added to the principal
 * Compound chocolate, an inexpensive chocolate substitute that uses cocoa but excludes cocoa butter

Proper names

 * The Compound (book), a 2008 young adult novel by S. A. Bodeen
 * Compound (company), a venture capital firm previously known as Metamorphic Ventures
 * Eisenhuth Horseless Vehicle Company, or Compound, a former US automobile manufacturer

title: Compound


text:
Citizenship

Citizenship is a membership and allegiance to a sovereign state.

Though citizenship is often legally conflated with nationality in today's Anglo-Saxon world, international law does not usually use the term citizenship to refer to nationality,  these two notions being conceptually different dimensions of collective membership.

Generally citizenships have no expiration and allow persons to work, reside and vote in the polity, as well as identify with the polity, possibly acquiring a passport. Though through discriminatory laws, like disfranchisement and outright apartheid citizens have been made second-class citizens. Historically, populations of states were mostly subjects, while citizenship was a particular status which originated in the rights of urban populations, like the rights of the male public of cities and republics, particularly ancient city-states, giving rise to a civitas and the social class of the burgher or bourgeoisie. Since then states have expanded the status of citizenship to most of their national people, while the extent of citizen rights remain contested.

Determining factors
A person can be recognized as a citizen on a number of bases.
 * Nationality. Nationality and citizenship are generally indissociable, citizenship being in most cases a consequence of nationality.
 * Place of residence. In some countries, foreign residents have citizenship rights and can vote.
 * Citizenship by honorary conferment. This type of citizenship is conferred to an individual as a sign of honour.
 * Excluded categories. In most countries, minors are not considered as full citizens. In the past, there have been exclusions on entitlement to citizenship on grounds such as skin color, ethnicity, sex, land ownership status, and free status (not being a slave). Most of these exclusions no longer apply in most places. Modern examples include some Gulf countries which rarely grant citizenship to non-Muslims, e.g. Qatar is known for granting citizenship to foreign athletes, but they all have to profess the Islamic faith in order to receive citizenship. The United States grants citizenship to those born as a result of reproductive technologies, and internationally adopted children born after February 27, 1983. Some exclusions still persist for internationally adopted children born before February 27, 1983, even though their parents meet citizenship criteria.

Responsibilities of a citizen
Every citizen has obligations that are required by law and some responsibilities that benefit the community. Obeying the laws of a country and paying taxes are some of the obligations required of citizens by law. Voting and community services form part of responsibilities of a citizen that benefits the community.

The Constitution of Ghana (1992), Article 41, obligates citizens to promote the prestige and good name of Ghana and respect the symbols of Ghana. Examples of national symbols includes the Ghanaian flag, coat of arms, money, and state sword. These national symbols must be treated with respect and high esteem by citizens since they best represent Ghanaians.

Apart from responsibilities, citizens also have rights. Some of the rights are the right to pursue life, liberty and happiness, the right to worship, right to run for elected office and right to express oneself.

Polis
Many thinkers such as Giorgio Agamben in his work extending the biopolitical framework of Foucault's History of Sexuality in the book, Homo Sacer, point to the concept of citizenship beginning in the early city-states of ancient Greece, although others see it as primarily a modern phenomenon dating back only a few hundred years and, for humanity, that the concept of citizenship arose with the first laws. Polis meant both the political assembly of the city-state as well as the entire society. Citizenship concept has generally been identified as a western phenomenon. There is a general view that citizenship in ancient times was a simpler relation than modern forms of citizenship, although this view has come under scrutiny. The relation of citizenship has not been a fixed or static relation but constantly changed within each society, and that according to one view, citizenship might "really have worked" only at select periods during certain times, such as when the Athenian politician Solon made reforms in the early Athenian state. Citizenship was also contingent on a variety of biopolitical assemblages, such as the bioethics of emerging Theo-Philosophical traditions. It was necessary to fit Aristotle's definition of the besouled (the animate) to obtain citizenship: neither the sacred olive tree nor spring would have any rights.

An essential part of the framework of Greco-Roman ethics is the figure of Homo Sacer or the bare life.

Historian Geoffrey Hosking in his 2005 Modern Scholar lecture course suggested that citizenship in ancient Greece arose from an appreciation for the importance of freedom. Hosking explained: "It can be argued that this growth of slavery was what made Greeks particularly conscious of the value of freedom. After all, any Greek farmer might fall into debt and therefore might become a slave, at almost any time ... When the Greeks fought together, they fought in order to avoid being enslaved by warfare, to avoid being defeated by those who might take them into slavery. And they also arranged their political institutions so as to remain free men."

Slavery permitted slave-owners to have substantial free time and enabled participation in public life. Polis citizenship was marked by exclusivity. Inequality of status was widespread; citizens (πολίτης politēs < πόλις 'city') had a higher status than non-citizens, such as women, slaves, and resident foreigners (metics). The first form of citizenship was based on the way people lived in the ancient Greek times, in small-scale organic communities of the polis. The obligations of citizenship were deeply connected to one's everyday life in the polis. These small-scale organic communities were generally seen as a new development in world history, in contrast to the established ancient civilizations of Egypt or Persia, or the hunter-gatherer bands elsewhere. From the viewpoint of the ancient Greeks, a person's public life could not be separated from their private life, and Greeks did not distinguish between the two worlds according to the modern western conception. The obligations of citizenship were deeply connected with everyday life. To be truly human, one had to be an active citizen to the community, which Aristotle famously expressed: "To take no part in the running of the community's affairs is to be either a beast or a god!" This form of citizenship was based on the obligations of citizens towards the community, rather than rights given to the citizens of the community. This was not a problem because they all had a strong affinity with the polis; their own destiny and the destiny of the community were strongly linked. Also, citizens of the polis saw obligations to the community as an opportunity to be virtuous, it was a source of honor and respect. In Athens, citizens were both rulers and ruled, important political and judicial offices were rotated and all citizens had the right to speak and vote in the political assembly.

Roman ideas
In the Roman Empire, citizenship expanded from small-scale communities to the entirety of the empire. Romans realized that granting citizenship to people from all over the empire legitimized Roman rule over conquered areas. Roman citizenship was no longer a status of political agency, as it had been reduced to a judicial safeguard and the expression of rule and law. Rome carried forth Greek ideas of citizenship such as the principles of equality under the law, civic participation in government, and notions that "no one citizen should have too much power for too long", but Rome offered relatively generous terms to its captives, including chances for lesser forms of citizenship. If Greek citizenship was an "emancipation from the world of things", the Roman sense increasingly reflected the fact that citizens could act upon material things as well as other citizens, in the sense of buying or selling property, possessions, titles, goods. One historian explained:

"The person was defined and represented through his actions upon things; in the course of time, the term property came to mean, first, the defining characteristic of a human or other being; second, the relation which a person had with a thing; and third, the thing defined as the possession of some person."

Roman citizenship reflected a struggle between the upper-class patrician interests against the lower-order working groups known as the plebeian class. A citizen came to be understood as a person "free to act by law, free to ask and expect the law's protection, a citizen of such and such a legal community, of such and such a legal standing in that community". Citizenship meant having rights to have possessions, immunities, expectations, which were "available in many kinds and degrees, available or unavailable to many kinds of person for many kinds of reason". The law itself was a kind of bond uniting people. Roman citizenship was more impersonal, universal, multiform, having different degrees and applications.

Middle Ages
During the European Middle Ages, citizenship was usually associated with cities and towns (see medieval commune), and applied mainly to middle-class folk. Titles such as burgher, grand burgher (German Großbürger) and the bourgeoisie denoted political affiliation and identity in relation to a particular locality, as well as membership in a mercantile or trading class; thus, individuals of respectable means and socioeconomic status were interchangeable with citizens.

During this era, members of the nobility had a range of privileges above commoners (see aristocracy), though political upheavals and reforms, beginning most prominently with the French Revolution, abolished privileges and created an egalitarian concept of citizenship.

Renaissance
During the Renaissance, people transitioned from being subjects of a king or queen to being citizens of a city and later to a nation. Each city had its own law, courts, and independent administration. And being a citizen often meant being subject to the city's law in addition to having power in some instances to help choose officials. City dwellers who had fought alongside nobles in battles to defend their cities were no longer content with having a subordinate social status but demanded a greater role in the form of citizenship. Membership in guilds was an indirect form of citizenship in that it helped their members succeed financially. The rise of citizenship was linked to the rise of republicanism, according to one account, since independent citizens meant that kings had less power. Citizenship became an idealized, almost abstract, concept, and did not signify a submissive relation with a lord or count, but rather indicated the bond between a person and the state in the rather abstract sense of having rights and duties.

Modern times
The modern idea of citizenship still respects the idea of political participation, but it is usually done through "elaborate systems of political representation at a distance" such as representative democracy. Modern citizenship is much more passive; action is delegated to others; citizenship is often a constraint on acting, not an impetus to act. Nevertheless, citizens are usually aware of their obligations to authorities and are aware that these bonds often limit what they can do.

United States
From 1790 until the mid-twentieth century, United States law used racial criteria to establish citizenship rights and regulate who was eligible to become a naturalized citizen. The Naturalization Act of 1790, the first law in U.S. history to establish rules for citizenship and naturalization, barred citizenship to all people who were not of European descent, stating that "any alien being a free white person, who shall have resided within the limits and under the jurisdiction of the United States for the term of two years, maybe admitted to becoming a citizen thereof."

Under early U.S. laws, African Americans were not eligible for citizenship. In 1857, these laws were upheld in the US Supreme Court case Dred Scott v. Sandford, which ruled that "a free negro of the African race, whose ancestors were brought to this country and sold as slaves, is not a 'citizen' within the meaning of the Constitution of the United States," and that "the special rights and immunities guaranteed to citizens do not apply to them."

It was not until the abolition of slavery following the American Civil War that African Americans were granted citizenship rights. The 14th Amendment to the U.S. Constitution, ratified on July 9, 1868, stated that "all persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside." Two years later, the Naturalization Act of 1870 would extend the right to become a naturalized citizen to include "aliens of African nativity and to persons of African descent".

Despite the gains made by African Americans after the Civil War, Native Americans, Asians, and others not considered "free white persons" were still denied the ability to become citizens. The 1882 Chinese Exclusion Act explicitly denied naturalization rights to all people of Chinese origin, while subsequent acts passed by the US Congress, such as laws in 1906, 1917, and 1924, would include clauses that denied immigration and naturalization rights to people based on broadly defined racial categories. Supreme Court cases such as Ozawa v. the United States (1922) and U.S. v. Bhagat Singh Thind (1923), would later clarify the meaning of the phrase "free white persons," ruling that ethnically Japanese, Indian, and other non-European people were not "white persons", and were therefore ineligible for naturalization under U.S. law.

Native Americans were not granted full US citizenship until the passage of the Indian Citizenship Act in 1924. However, even well into the 1960s, some state laws prevented Native Americans from exercising their full rights as citizens, such as the right to vote. In 1962, New Mexico became the last state to enfranchise Native Americans.

It was not until the passage of the Immigration and Nationality Act of 1952 that the racial and gender restrictions for naturalization were explicitly abolished. However, the act still contained restrictions regarding who was eligible for US citizenship and retained a national quota system which limited the number of visas given to immigrants based on their national origin, to be fixed "at a rate of one-sixth of one percent of each nationality's population in the United States in 1920". It was not until the passage of the Immigration and Nationality Act of 1965 that these immigration quota systems were drastically altered in favor of a less discriminatory system.

Union of the Soviet Socialist Republics
The 1918 constitution of revolutionary Russia granted citizenship to any foreigners who were living within the Russian Soviet Federative Socialist Republic, so long as they were "engaged in work and [belonged] to the working class." It recognized "the equal rights of all citizens, irrespective of their racial or national connections" and declared oppression of any minority group or race "to be contrary to the fundamental laws of the Republic." The 1918 constitution also established the right to vote and be elected to soviets for both men and women "irrespective of religion, nationality, domicile, etc. [...] who shall have completed their eighteenth year by the day of the election." The later constitutions of the USSR would grant universal Soviet citizenship to the citizens of all member republics in concord with the principles of non-discrimination laid out in the original 1918 constitution of Russia.

Nazi Germany
Nazism, the German variant of twentieth-century fascism, classified inhabitants of the country into three main hierarchical categories, each of which would have different rights in relation to the state: citizens, subjects, and aliens. The first category, citizens, were to possess full civic rights and responsibilities. Citizenship was conferred only on males of German (or so-called "Aryan") heritage who had completed military service, and could be revoked at any time by the state. The Reich Citizenship Law of 1935 established racial criteria for citizenship in the German Reich, and because of this law Jews and others who could not "prove German racial heritage" were stripped of their citizenship.

The second category, subjects, referred to all others who were born within the nation's boundaries who did not fit the racial criteria for citizenship. Subjects would have no voting rights, could not hold any position within the state, and possessed none of the other rights and civic responsibilities conferred on citizens. All women were to be conferred "subject" status upon birth, and could only obtain "citizen" status if they worked independently or if they married a German citizen (see women in Nazi Germany).

The final category, aliens, referred to those who were citizens of another state, who also had no rights.

In 2021, the German government passed Article 116 (2) of the Basic Law, which entitles the restoration of citizenship to individuals who had their German citizenship revoked "on political, racial, or religious grounds" between 30 January 1933 and 8 May 1945. This also entitles their descendants to German citizenship.

Israel
The primary principles of Israeli citizenship is jus sanguinis (citizenship by descent) for Jews and jus soli (citizenship by place of birth) for others.

Different senses
Many theorists suggest that there are two opposing conceptions of citizenship: an economic one, and a political one. For further information, see History of citizenship. Citizenship status, under social contract theory, carries with it both rights and duties. In this sense, citizenship was described as "a bundle of rights -- primarily, political participation in the life of the community, the right to vote, and the right to receive certain protection from the community, as well as obligations." Citizenship is seen by most scholars as culture-specific, in the sense that the meaning of the term varies considerably from culture to culture, and over time. In China, for example, there is a cultural politics of citizenship which could be called "peopleship", argued by an academic article.

How citizenship is understood depends on the person making the determination. The relation of citizenship has never been fixed or static, but constantly changes within each society. While citizenship has varied considerably throughout history, and within societies over time, there are some common elements but they vary considerably as well. As a bond, citizenship extends beyond basic kinship ties to unite people of different genetic backgrounds. It usually signifies membership in a political body. It is often based on or was a result of, some form of military service or expectation of future service. It usually involves some form of political participation, but this can vary from token acts to active service in government.

It generally describes a person with legal rights within a given political order. It almost always has an element of exclusion, meaning that some people are not citizens and that this distinction can sometimes be very important, or not important, depending on a particular society. Citizenship as a concept is generally hard to isolate intellectually and compare with related political notions since it relates to many other aspects of society such as the family, military service, the individual, freedom, religion, ideas of right, and wrong, ethnicity, and patterns for how a person should behave in society. When there are many different groups within a nation, citizenship may be the only real bond that unites everybody as equals without discrimination—it is a "broad bond" linking "a person with the state" and gives people a universal identity as a legal member of a specific nation.

Modern citizenship has often been looked at as two competing underlying ideas:

 * The liberal-individualist or sometimes liberal conception of citizenship suggests that citizens should have entitlements necessary for human dignity. It assumes people act for the purpose of enlightened self-interest. According to this viewpoint, citizens are sovereign, morally autonomous beings with duties to pay taxes, obey the law, engage in business transactions, and defend the nation if it comes under attack, but are essentially passive politically, and their primary focus is on economic betterment. This idea began to appear around the seventeenth and eighteenth centuries and became stronger over time, according to one view. According to this formulation, the state exists for the benefit of citizens and has an obligation to respect and protect the rights of citizens, including civil rights and political rights. It was later that so-called social rights became part of the obligation for the state.

 * The civic-republican or sometimes classical or civic humanist conception of citizenship emphasizes man's political nature and sees citizenship as an active process, not a passive state or legal marker. It is relatively more concerned that government will interfere with popular places to practice citizenship in the public sphere. Citizenship means being active in government affairs. According to one view, most people today live as citizens according to the liberal-individualist conception but wished they lived more according to the civic-republican ideal. An ideal citizen is one who exhibits "good civic behavior". Free citizens and a republic government are "mutually interrelated." Citizenship suggested a commitment to "duty and civic virtue".

Responsibilities of citizens

Responsibility is an action that individuals of a state or country must take note of in the interest of a common good. These responsibilities can be categorised into personal and civic responsibilities.

Scholars suggest that the concept of citizenship contains many unresolved issues, sometimes called tensions, existing within the relation, that continue to reflect uncertainty about what citizenship is supposed to mean. Some unresolved issues regarding citizenship include questions about what is the proper balance between duties and rights. Another is a question about what is the proper balance between political citizenship versus social citizenship. Some thinkers see benefits with people being absent from public affairs, since too much participation such as revolution can be destructive, yet too little participation such as total apathy can be problematic as well. Citizenship can be seen as a special elite status, and it can also be seen as a democratizing force and something that everybody has; the concept can include both senses. According to sociologist Arthur Stinchcombe, citizenship is based on the extent that a person can control one's own destiny within the group in the sense of being able to influence the government of the group. One last distinction within citizenship is the so-called consent descent distinction, and this issue addresses whether citizenship is a fundamental matter determined by a person choosing to belong to a particular nation––by their consent––or is citizenship a matter of where a person was born––that is, by their descent.

International
Some intergovernmental organizations have extended the concept and terminology associated with citizenship to the international level, where it is applied to the totality of the citizens of their constituent countries combined. Citizenship at this level is a secondary concept, with rights deriving from national citizenship.

European Union
The Maastricht Treaty introduced the concept of citizenship of the European Union. Article 17 (1) of the Treaty on European Union stated that: "Citizenship of the Union is hereby established. Every person holding the nationality of a Member State shall be a citizen of the Union. Citizenship of the Union shall be additional to and not replace national citizenship."

An agreement is known as the amended EC Treaty established certain minimal rights for European Union citizens. Article 12 of the amended EC Treaty guaranteed a general right of non-discrimination within the scope of the Treaty. Article 18 provided a limited right to free movement and residence in the Member States other than that of which the European Union citizen is a national. Articles 18-21 and 225 provide certain political rights.

Union citizens have also extensive rights to move in order to exercise economic activity in any of the Member States which predate the introduction of Union citizenship.

Mercosur
Citizenship of the Mercosur is granted to eligible citizens of the Southern Common Market member states. It was approved in 2010 through the Citizenship Statute and should be fully implemented by the member countries in 2021 when the program will be transformed in an international treaty incorporated into the national legal system of the countries, under the concept of "Mercosur Citizen".

Commonwealth
The concept of "Commonwealth Citizenship" has been in place ever since the establishment of the Commonwealth of Nations. As with the EU, one holds Commonwealth citizenship only by being a citizen of a Commonwealth member state. This form of citizenship offers certain privileges within some Commonwealth countries:
 * Some such countries do not require tourist visas of citizens of other Commonwealth countries or allow some Commonwealth citizens to stay in the country for tourism purposes without a visa for longer than citizens of other countries.
 * In some Commonwealth countries, resident citizens of other Commonwealth countries are entitled to political rights, e.g., the right to vote in local and national elections and in some cases even the right to stand for election.
 * In some instances the right to work in any position (including the civil service) is granted, except for certain specific positions, such as in the defense departments, Governor-General or President or Prime Minister.
 * In the United Kingdom, all Commonwealth citizens legally residing in the country can vote and stand for office at all elections.

Although Ireland was excluded from the Commonwealth in 1949 because it declared itself a republic, Ireland is generally treated as if it were still a member. Legislation often specifically provides for equal treatment between Commonwealth countries and Ireland and refers to "Commonwealth countries and Ireland". Ireland's citizens are not classified as foreign nationals in the United Kingdom.

Canada departed from the principle of nationality being defined in terms of allegiance in 1921. In 1935 the Irish Free State was the first to introduce its own citizenship. However, Irish citizens were still treated as subjects of the Crown, and they are still not regarded as foreign, even though Ireland is not a member of the Commonwealth. The Canadian Citizenship Act of 1946 provided for a distinct Canadian Citizenship, automatically conferred upon most individuals born in Canada, with some exceptions, and defined the conditions under which one could become a naturalized citizen. The concept of Commonwealth citizenship was introduced in 1948 in the British Nationality Act 1948. Other dominions adopted this principle such as New Zealand, by way of the British Nationality and New Zealand Citizenship Act 1948.

Subnational
Citizenship most usually relates to membership of the nation-state, but the term can also apply at the subnational level. Subnational entities may impose requirements, of residency or otherwise, which permit citizens to participate in the political life of that entity or to enjoy benefits provided by the government of that entity. But in such cases, those eligible are also sometimes seen as "citizens" of the relevant state, province, or region. An example of this is how the fundamental basis of Swiss citizenship is a citizenship of an individual commune, from which follows citizenship of a canton and of the Confederation. Another example is Åland where the residents enjoy special provincial citizenship within Finland, hembygdsrätt.

The United States has a federal system in which a person is a citizen of their specific state of residence, such as New York or California, as well as a citizen of the United States. State constitutions may grant certain rights above and beyond what is granted under the United States Constitution and may impose their own obligations including the sovereign right of taxation and military service; each state maintains at least one military force subject to national militia transfer service, the state's national guard, and some states maintain a second military force not subject to nationalization.

Education
"Active citizenship" is the philosophy that citizens should work towards the betterment of their community through economic participation, public, volunteer work, and other such efforts to improve life for all citizens. In this vein, citizenship education is taught in schools, as an academic subject in some countries. By the time children reach secondary education there is an emphasis on such unconventional subjects to be included in an academic curriculum. While the diagram on citizenship to the right is rather facile and depthless, it is simplified to explain the general model of citizenship that is taught to many secondary school pupils. The idea behind this model within education is to instill in young pupils that their actions (i.e. their vote) affect collective citizenship and thus in turn them.

Republic of Ireland
It is taught in the Republic of Ireland as an exam subject for the Junior Certificate. It is known as Civic, Social and Political Education (CSPE). A new Leaving Certificate exam subject with the working title 'Politics & Society' is being developed by the National Council for Curriculum and Assessment (NCCA) and is expected to be introduced to the curriculum sometime after 2012.

United Kingdom
Citizenship is offered as a General Certificate of Secondary Education (GCSE) course in many schools in the United Kingdom. As well as teaching knowledge about democracy, parliament, government, the justice system, human rights and the UK's relations with the wider world, students participate in active citizenship, often involving a social action or social enterprise in their local community.
 * Citizenship is a compulsory subject of the National Curriculum in state schools in England for all pupils aged 11–16. Some schools offer a qualification in this subject at GCSE and A level. All state schools have a statutory requirement to teach the subject, assess pupil attainment and report student's progress in citizenship to parents.
 * In Wales the model used is personal and social education.
 * Citizenship is not taught as a discrete subject in Scottish schools, but is a cross-curricular strand of the Curriculum for Excellence. However they do teach a subject called "Modern Studies" which covers the social, political and economic study of local, national and international issues.
 * Citizenship is taught as a standalone subject in all state schools in Northern Ireland and most other schools in some forms from year 8 to 10 prior to GCSEs. Components of Citizenship are then also incorporated into GCSE courses such as 'Learning for Life and Work'.

Criticism
The concept of citizenship is criticized by open borders advocates, who argue that it functions as a caste, feudal, or apartheid system in which people are assigned dramatically different opportunities based on the accident of birth. It is also criticized by some libertarians, especially anarcho-capitalists. In 1987, moral philosopher Joseph Carens argued that "citizenship in Western liberal democracies is the modern equivalent of feudal privilege—an inherited status that greatly enhances one's life chances. Like feudal birthright privileges, restrictive citizenship is hard to justify when one thinks about it closely".

title: Citizenship