Xah Lee, 2007, 2011-01, 2011-03-26, 2011-06-02
This page discusses some difference of keysets and their function in Apple Keyboards and IBM PC keyboard.
A typical PC keyboard's keys.
A typical Apple keyboard's keys.
On the PC keyboard, you have the Ctrl (Control), Win (Windows/Start), Alt (alternate) keys.
On Apple keyboard, you have Ctrl, ⌥ Opt (alt/option), ⌘ (command) keys.
Although both Mac and Windows have Ctrl and Alt keys, but their use is different.
The Control Key in Windows is mostly used forkeyboard shortcuts. For example, Copy is 【Ctrl+c】, Paste is 【Ctrl+v】. (On the Mac, Cmd key is used for keyboard shortcuts. Copy is 【⌘+c】, Paste is 【⌘+v】)
The Control key under Mac is rarely used. When used in applications, it often function as a modifier in combination with other modifier keys. For example, 【Ctrl+⌘+z】 in iTunes will iconify the window. Under OS X, the Control is also used for some Emacs's keybindings. For example, 【Ctrl+f】 moves cursor forward.
The Alt key in MS Windows has 3 different uses:
The menu key on Microsoft Natural Ergonomic Keyboard 4000.
The Menu key, also called Application key, exists on PC keyboard only. Typically only on the right side. It is used for Context Menu, but it is intended to be application specific. The key's function is usually the same as pressing mouse's right button, or pressing 【Shift+F10】 in most applications.
The Option key (often labeled option, ⌥, alt) is used to type special characters, such as “• ™ ©”. For example, 【⌥+8】 will type the bullet character “•”. (See: Mac OS X Keyboard Viewer and Unicode.)
The Option key is also used as a modifier key together with the Command key. For example, in 【⌘+⌥+h】 invokes the command “Hide Others” in all Apple applications.
The Windows key invokes the Start menu under Microsoft Windows. When pressed with letter key, it invoke a shortcut. For example, 【Win+d】 gets you the desktop. (See: Windows Shortcuts.)
The Command key (labeled “⌘” or “cmd”) on the Mac is used as a modifier key to invoke shortcuts. For example, 【⌘+c】 is Copy. It is similar to MS Window's use of the Ctrl key.
On Apple's keyboards, there is the Return key on the main section, and there is a Enter key on the numeric keypad. These 2 keys send different signals.
On PC, both these keys are labeled “Enter”. These two Enter keys on PC send different key signals.
The difference between Apple and PC here is probably just labeling.
On the Mac, the Return key and the Enter key usually serve the same purpose, but sometimes different. For example, in Mathematica since at least version 2 (early 1990s), the Return key is used to insert a line break, but the Enter is used to execute the code in the current cell (Shift+Return does the same). On many chat clients such as Adium and Colloquy (IRC client), user can set it up in so that the Return will insert a line break while the Enter key will send out the message.
PC keyboard's keys. The “Backspace” is labeled “delete” on Apple keyboards. The Delete key is labeled “delete⌦” on Apple. The PrtScn/SysRq, ScrLk, Pause/Break is F13 F14 F15 on Apple's keyboards.
On PC keyboards, there is a Backspace key on the main section, and a Delete key (sometimes labeled Del) on the Home/End key cluster.
On Apple keyboards, both of these are labeled “delete”. This difference is just the key labeling.
The key located at the upper right corner labled Backspace or Delete are used the same way in both OS X and Windows when in a text editing application. Specifically, it is used to delete texts to the left of the cursor. However, MS Windows also use the key to “go back”, such as going to a previous visited page in a browser. Only in recent years, Mac OS X's browsers also started to let the key do the same thing.
The key located to the left of the End key, labeled Delete or Del, have different purposes than the Backspace key.
On Windows, Del is often used to actually delete things. For example, selecting a file, pressing Del will put the file to the “Recycle Bin”. In a text editor, the key will delete to the right of the cursor.
On the Mac, from early 1990s to 2006, the Del key is almost never used, even in text editors. When there is a function assigned to it, it is used to delete to the right of the cursor.
On PC keyboards, there is the Insert key (sometimes labeled Ins). On Apple keyboards, this key is labeled Help.
I think the difference is NOT just labeling; they may actually send different key signals, but the OS or keyboard driver software may interpret them so to user it's the same.
The PC has these keys: PrtScn/SysRq, ScrLk, Pause/Break.
Apple's keyboards do not have these keys. On some Apple keyboards, it have F13, F14, F15 instead. “Apple Keyboard with Numeric Keypad” of 2009, has F16 to F19.
These keys have old history back to the 1980's (or earlier) and in general are not used since 1990, except on Windows the PrtScn key is for screenshot. These keys are basically never used in Mac (as i know of from 1992 to 2007), except that in recent years with OS X, Apple started to use F14 and F15 to decrease/increase the display's brightness.
I think the ScrLk, Pause/Break.
I'm not sure if the the two sets {PrtScn ScrLk Break} vs {F13 F14 F15} sends the same signals. In anycase, in Mac OS X, they seems to behave the same.
On the Numeric keypad. Apple's numeric keypad added a equal = key. (PC's + key takes 2 key spaces) Because of this change, the arrangement of the arithmetic operator keys are a little different.
Also, the “Number Lock” key on PC keyboard is “Clear” on Apple keyboard. Apple keyboard does not have Number Lock toggle. (a excellent change.)