Editing Function keys

{{About|the general purpose keys|the hardware layer modifier key|function key}}

'''Function keys''' are general-purpose numbered [[Soft key|softkeys]] found on the majority of computer keyboards. The number of function keys varies between computer systems; IBM-compatible computers typically have 12, while Macintosh computers have more: 15 on the [[Matias Tactile Pro 3]], and 19 on the aluminium [[Apple Aluminium Keyboard|Apple Keyboard]].

Function keys are typically labelled in the sequence { F1, F2, F3 … } but some keyboards start counting at zero.

'''Programmable function''' keys on [[:Category:programmable keyboards|programmable keyboards]] are typically labelled from PF1 upwards. The behaviour of function keys is operating system or software defined, while programmable function keys have user-defined behaviour, for example macro execution.

==Count==
Ten function keys was the typical amount on older keyboards; the [[IBM Model M]] increased the count to 12, and Apple have since increased the number further, variously using zero, 15, 12, 16 and 19<ref>[http://www.mauseum.net/Tastatura/ Tastatur / Keyboard 1968 - 2007] at Mauseum.net</ref>. Conversely, the [[Commodore 64]] only had four physical keys, labelled f 1/f 2 to f 7 /f 8, an approach found on several manufacturers' products.

<gallery widths=250 heights=187>
File:IBM Model F AT.jpg|[[IBM Model F]] with 10 function keys along the side
File:Amiga 2000 US.JPG|[[Amiga]] 2000 keyboard with 10 function keys along the top
File:Macintosh F15 to F19.jpg|[[Apple Aluminium Keyboard|Macintosh keyboard]] with 19 function keys
File:G80-0528HAU NCR 001.jpg|[[Cherry G80-0528]] with 30 function keys
</gallery>

==Position==
Function keys are typically placed on the top row of keys. However, the placement has varied over time.

===Side===
Function keys were frequently placed on the left-hand side of early keyboards, in two columns. Side layout has recently made a comeback with [[macro keys]] on gaming-orientated keyboards.

<gallery widths=250 heights=117>
File:CherryG80-0915.jpg|[[Commodore International|Commodore]]-branded [[Cherry G80-0915]]
</gallery>

===Top===
The [[IBM Model M]] is noted for moving the function keys from the left to the top, although it was not the first computer to feature them in this position.

<gallery widths=250 heights=187>
File:252309_10151033065251203_1606697737_n.jpg|IBM advert showing their change to top placement and the addition of F11 and F12
File:Dell Old Logo.jpg|Top-row placement on a [[Dell AT101]]
</gallery>

==Arrangement==
<gallery widths=250 heights=187>
File:IBM Space Saving Keyboard with RGB modifiers.jpg|Standard grouping is single row, 4 + 4 + 4
File:Sony NEWS NWP-5461 Front.JPG|[[Sony NEWS NWP-5461]] grouped as 5 + 5 + 2
File:MD01B0 - Front.jpg|[[Topre Short-throw]] grouped as 6×2
File:Datalux6.jpg|4×3 cluster on a [[Datalux SpaceSaver]]
File:Focus5001USlayout.jpg|[[Focus FK-5001]] with 2×5 cluster as well as a single row arranged as 3 + 3 + 3 + 3
</gallery>

==Numbering==
<gallery widths=250 heights=187>
File:1388032.jpg|Standard numbering is F1–12
File:G80-2100HDF 001.jpg|[[Cherry G80-2100]] with static F1–10 and [[Relegendable key|relegendable]] PF1–24
File:BBC Micro function keys.jpg|BBC Micro function keys ''f''0–9 with function key legend strip
</gallery>

==Secondary functionality==
On some keyboards, the conventional functionality—scancodes for F1–12—are secondary in nature to some other functionality. An additional key such as [[Fn key|Fn]] must be held to trigger F1–12. In the case of a laptop, this may be reversible within the BIOS, such that (for example, with a Dell Inspiron 15) pressing the F5 key will again refresh a web page instead of increase the screen brightness.

<gallery widths=250 heights=187>
File:Logitech Y-RJ20 -- function keys.jpg|F1–12 relegation on a [[Logitech Cordless Keyboard (Y-RJ20)|Logitech Y-RJ20]]
</gallery>

==Bindings==
===Microsoft Windows===
Common bindings for [[Microsoft Windows|Windows]] applications are:

{|
|-
| '''F1''' || Help
|-
| '''F2''' || Rename the selected item
|-
| '''F3''' || Find
|-
| '''F5''' || Refresh
|-
| '''F6''' || Switch panel
|-
| '''F10''' || Focus the menu bar (the same as pressing [[Alt key|Alt]]; shift-F10 opens a context menu the same as the [[menu key]])
|}

===Macintosh===
<gallery widths=250 heights=167>
File:Apple_M0115_function_labels.jpg | Traditional Macintosh function key bindings on F1–4
</gallery>

==See also==
* [[Fun cluster]]
* [[Fn key]]

==References==
<references />

[[Category:Keyboard keys]]