Editing Physical keyboard layout (section)

==Common layouts==
===F XT===
[[File:Physical layout -- F XT.svg|centre]]

As used by the [[IBM Personal Computer keyboard]] and [[:Category:Clones of the IBM Model F|many clone keyboards]].

Note the vertical Return key and the extra key between left shift and the first alphanumeric key, reminiscent of the later ISO layout.

===F AT===
[[File:Physical layout -- F AT.svg|centre]]

As used by the [[IBM Personal Computer AT keyboard]] and [[:Category:Clones of the IBM Model F|many clone keyboards]].

===ANSI 101===
[[File:Physical layout -- ANSI 101.svg|centre]]

Introduced by the [[IBM Enhanced Keyboard]], this became the standard US layout. Keyboards designed in the US took this form, while many keyboards marketed in the US by Asian companies used the Asian 101 layout.

Around 1995 Microsoft added three more keys to the keyboard, inserted between Ctrl and Alt: two [[Windows key]]s, on the left and right sides, and the [[Menu key]] on the right. The layout remains otherwise unchanged to this day, although many keyboards have made unconventional adaptations. One adaptation, used by the [[Microsoft Natural Keyboard Elite]] and others, rearranges the 3×2 navigation block into 2×3.

===ISO 102===
[[File:Physical layout -- ISO 102.svg|centre]]

Widely used in Europe, with the Netherlands being an exception, as they switched to the US ANSI layout. This layout may have also originated with the IBM Enhanced keyboard. This layout was likewise adapted by Microsoft in the same manner as ANSI.

===Asian 101===
[[File:Physical layout -- Asian 101.svg|centre]]

"Asian" layout widely used by Asian manufacturers such as [[Chicony]]. The "big Asian" Enter key (shortened to "big-ass") is found on these keyboards. Backspace is a single unit. [[NMB RT-100/RT-8200 series]] keyboards (models ending "+") also used this layout; this may be because the manufacturer Hi-Tek was bought by the Japanese company Minebea, but it may also be a holdover from earlier designs, as the Asian 101 layout itself appears to have been derived from the [[IBM Model F]] AT.

Some manufacturers such as NMB produced ISO keyboards for the European market. Other manufacturers such as Nan Tan adopted Asian 101 to create a hybrid Asian/ISO keyboard, with the same large Enter key but with an extra key added to the right of left shift.

Examples:
*[[Datacomp DFK-501F/502F]]
*[[Chicony KB-5161]]
*[[Chicony KB-5181]]
*[[NMB RT-100/RT-8200 series]]
*[[NTC KB-6151]]
*[[NTC KB-6251]]

An alternative approach, Asian 102 as seen below, was to use a 102-key layout for both markets, with one key left blank in logical layouts that only used 102 keys. This approach allows for Backspace to remain a full 2 units. Another 2-unit Backspace 101-key variant exists where right shift is reduced in size to allow backslash to be moved to its right, as found in the [[Tai-Hao TH-5539]] series.

===Asian 102===
[[File:Physical layout -- Asian 102.svg|centre]]

Used by Monterey, KPT, Focus and others, Asian 102 is used by both 101-key and 102-key keyboards. A 1-unit key is inserted on each side in between Ctrl and Alt. On US keyboards, the right-hand key is backslash and the left-hand key is blank. On UK keyboards, backslash is moved to the left-hand key (mimicking ISO) and # is placed on the right-hand key to allow shift+3 to be £. Other European languages are adapted similarly.

Examples:
*Older [[Focus FK-2001]]
*[[Focus FK-8000]]
*[[KPT KPT-102]]
*[[Monterey K101]]/K102

===Focus===
[[File:Physical layout -- Focus.svg|centre]]

The so-called "Focus" layout is an alternative to Asian 101, where right shift is divided instead of Backspace. While the [[JIS]] layout also features a split right shift, JIS keyboards place the extra key to the left of right shift, whereas the Focus layout puts the extra key to the right. The origin of the layout is not known, but it is most notable by its use by Focus.

Examples:
*[[BTC 5139]]
*[[Focus FK-555]]
*Some 101-key, and possibly all 104-key [[Focus FK-2001]]; Focus also used the Asian 102 layout as 101-key (Europe had the ISO [[Focus FK-2002|FK-2002]] instead)
*[[Lite-On SK-0002]]
*Some [[Tai-Hao TH-5539]] variants