British and American keyboards
There are two major keyboard layouts : the United States layout and the United Kingdom layout defined in BS 4822. Both are QWERTY layouts. Users in the United States do not frequently need to make use of the £ and € currency symbols, which are common needs in the United Kingdom and Ireland, although the $ symbol is also provided as standard on UK and Irish keyboards. In other countries which predominantly use English as a common working language, such as Australia, Canada, and New Zealand, the US keyboard is commonly used.
Windows keyboards
The UK variant of the Enhanced keyboard commonly used with personal computers designed for Microsoft Windows differs from the US layout as follows:- The UK keyboard has 1 more key than the U.S. keyboard
- The extra key is added next to the Enter key to accommodate and
- The Alt key to the right of the space bar is replaced by an AltGr key
- The takes the place vacated by the number sign on the key
- The takes the place vacated by tilde on the key
- * produces
- * produces
- is produced by and is shown as a secondary symbol
- and are swapped
- The key is moved to the left of the key
- The Enter key spans two rows, and is narrower to accommodate the #/~ key
- AltGr+vowel produces the acute accent variant of that vowel as needed for Irish. Diacritics used in Scots Gaelic and Welsh require the UK extended keyboard setting.
- Some UK keyboards do not label Backspace, Enter, Tab and Shift in words
However, in more recent editions of Windows, the number of 'settings' options was increased, allowing users to select the correct keyboard and language variety independently. For example, one is given a number of default options for locality that will usually correctly match keyboard and language variety. Further, even if the physical keyboard is not the same as the keyboard layout used on system, it can be changed without changing the language variety.
International or extended keyboard layouts
Since the default US keyboard layout in Microsoft Windows offers no way of inputting any sort of diacritic or accent, this makes it unsuitable for all but a handful of languages unless the US International layout is used. The US International layout changes the , , , , and keys into dead keys for producing accented characters: thus for example will produce. The US International layout also uses the right alt as a modifier to enter special characters.The equivalent mapping for UK/Irish keyboards is called the "UK Extended" layout which, if activated in settings, will allow the user to enter a wide variety of diacritics which are not accommodated by the standard UK/Irish layout. In particular, à,è,ì,ò,ù used in Scots Gaelic can be made, the ŵ and ŷ used in Welsh. Likewise, the Spanish and Portuguese letters ñ and õ can be made.
For more specialized uses, there is a facility in Windows for users to create a customized layout that may match their needs more precisely.
Apple Macintosh keyboards
The default U.S. layout on Apple Macintosh computers allows input of diacritical characters as the entire MacRoman character set is directly accessible. A U.S. international layout is also available.Macintosh keyboards for British typists makes use of an Apple-custom layout. This differs significantly from the British Standard BS 4822 layout found on most UK keyboards. Differences include:
- The and keys are swapped.
- The symbol is assigned to +, rather than +.
- The symbol is assigned to +, rather than a dedicated key.
- The and dedicated key is absent.
- The and dedicated key is present.
- The and, and the and keys are moved.
MacOS provides support for diacritics using either a "press and hold for pop-up menu" or a more extensive 'dead-key' facility.
Other keyboard layouts
Other operating systems can optionally re-map the keyboard layout or have different modifier keys.Under Unix/Linux the "Windows" key is often called the "Super" key and can be re-mapped by users for specific functionality but in most programs by default does nothing.
Some older Unix/Linux software, such as Emacs, uses the left Alt key as a "Meta" key, which harks back to older MIT or LISP computers.
ChromeOS uses the US and UK Windows layouts, except that the Caps-Lock key is labelled with a "fisheye" and by default acts as an "everything" search key.. The function-key row is also differently labelled. The UK-extended layout for ChromeOS is provided by a Chrome add-on, and provides ready access to a substantially greater repertoire of precomposed characters for western, central and eastern European languages.