Editing QWERTY (section)

==Computer keyboards==
[[File:Qwerty.svg|thumb|upright 1.5|A QWERTY keyboard layout variant that is used in the US. Some countries, such as the UK and Canada, use a slightly different QWERTY (the @ and " are switched in the UK and both have an [[AltGr]] ("alternate graphic") key rather than a right-hand [[Alt key]] {{snd}} as do most non-[[English language]] keyboards; see [[keyboard layout]]). ]]

The first computer terminals such as the Teletype were typewriters that could produce and be controlled by various computer codes. These used the QWERTY layouts and added keys such as [[Esc key|escape]] {{keypress|Esc}} which had special meanings to computers. Later keyboards added [[function key]]s and [[arrow keys]]. Since the standardization of [[personal computer]]s and [[Microsoft Windows|Windows]] after the 1980s, most full-sized computer keyboards have followed this standard (see drawing at right). This layout has a separate [[numeric keypad]] for data entry at the right, 12 function keys across the top, and a cursor section to the right and center with keys for {{keypress|[[Insert key|Insert]]}}, {{keypress|[[Delete key|Delete]]}}, {{keypress|[[Home key|Home]]}}, {{keypress|[[End key|End]]}}, {{keypress|[[Page Up and Page Down keys|Page Up]]}}, and {{keypress|[[Page Up and Page Down keys|Page Down]]}} with cursor arrows in an inverted-T shape.<ref>{{cite journal|last=Castillo|first=M.|title=QWERTY, @, &, #|journal=[[American Journal of Neuroradiology]]|date=2 September 2010|volume=32|issue=4|pages=613–614|doi=10.3174/ajnr.a2228|pmid=20813871|pmc=7965893 |doi-access=free | issn=0195-6108}}</ref>

===Diacritical marks===
QWERTY was designed for [[English language|English]], a language with accents ('[[diacritic]]s') appearing only in a few words of foreign origin.  The standard US keyboard has no provision for these at all; the need was later met by the so-called "[[#US-international|US-International]]" [[keyboard mapping]], which uses "[[dead key]]s" to type accents without having to add more physical keys. (The same principle is used in the standard US keyboard layout for [[macOS]], but in a different way). Most European (including UK) keyboards for PCs have an {{keypress|[[AltGr]]}} key ('Alternative Graphics' key,{{efn|Where this key is not provided, some layouts provide its equivalent using {{keypress|ctrl|alt}}+the letter to be accented, which can mean some [[Chorded keyboard|chord]]s that require additional manual dexterity.}} replaces the right Alt key) that enables easy access to the most common diacritics used in the territory where sold. For example, default keyboard mapping for the UK/Ireland keyboard has the diacritics used in [[Irish language|Irish]] but these are rarely printed on the keys; but to type the accents used in [[Welsh language|Welsh]] and [[Scots Gaelic]] requires the use of a "[[#United Kingdom (Extended) Layout|UK Extended]]" keyboard mapping and the dead key or [[compose key]] method. This arrangement applies to Windows, [[ChromeOS]] and [[Linux]]; macOS computers have different techniques. The US International and UK Extended mappings provide many of the diacritics needed for students of other European languages.

===Other keys and characters===
{{Main|Alt code|Compose key|Option key}}

Some QWERTY keyboards have [[alt code]]s, in which holding {{keypress|Alt}} while inputting a sequence of numbers on a numeric keypad allows the entry of special characters. For example, {{keypress|Alt}}+{{keypress|1}}{{keypress|6}}{{keypress|3}} results in ú (a Latin lowercase letter u with an acute accent).