Computer keyboards feature a range of key types that are grouped into regions according to their functions. Some key regions are optional and are left out of models to conserve space. The computer keyboard owes its pedigree to the typewriter, featuring a similar alphanumeric layout and key names. Computer keyboards can differ substantially from one another depending on the model. Laptop keyboards often omit keys or assign keys multiple uses to optimize space.
Every standard keyboard features alphanumeric keys, which are also called character keys. The alphanumeric region includes letter keys for the alphabet, the horizontal number keys and utility keys such as the space bar. While the alphanumeric keys are usually aligned, ergonomic keyboards may split the keys down the middle for comfortable two-handed typing.
Optional Numeric Keypad
A typical full keyboard includes a numeric keypad on the far right of the device. The numeric keypad is designed to resemble a calculator keypad, which makes it possible for people to type numbers faster than they can using the number keys in the alphanumeric section of the keyboard. Laptops and small form-factor keyboards often drop the numeric keypad to save space and add a toggle function to reassign alphanumeric keys to work like a numeric keypad.
Directional and Cursor Keys
Keyboards can include all or some of the directional and cursor keys, which are also referred to as navigation keys. The directional arrow keys are used to move the cursor or scroll a document. The cursor control keys are used to toggle character insert mode and quickly navigate between document pages.
Multimedia and Function Keys
Some keyboards include multimedia and function keys, which serve as task shortcuts. Multimedia keys are customized one-touch buttons that launch programs and adjust system volume. Laptops often employ a "Function" or "Fn" key that when pressed in conjunction with another key performs a special function such as adjusting the screen brightness.
Backlighting as an Option
High-end keyboards can may include backlights that illuminate the keyboard's keys when in use. Backlights are designed to make the keyboard easier to see in a dark room instead of relying on the light from the monitor. Backlights are usually toggled with a keyboard shortcut.
PC Versus Mac Keyboards
PCs and Macs use slightly different keyboards that feature some different keys and have somewhat different layouts. PCs have "Alt" and "Windows" keys whereas Macs have "Apple/Command" and "Option" keys. PCs use the word "Enter" and most Macs use the word "Return," but those two keys are functionally identical.