A keyboard is perhaps the simplest of all peripherals. Since it's inception, it is used in practically all interactive computer devices to some degree.
The most common style of keyboard layout is nicknamed QWERTY. A Typical Keyboard has 12 function keya (Early BBC Basic PC's had 18), Alphanumerical and Punctuation Character keys, Directional Keys, and most have a Number Pad.
Function Keys
Ctrl
Alt
Alt Gr
Shift
Windows Key
Menu Key
Keyboard Lock Keys
Num Lock
Caps Lock
Scroll Lock
Common Keyboard Keys
Insert
Home
Delete
End
Page Up
Page Down
Enter
Return
Backspace
Tab
Esc
Print Screen
Not-so-Common Keyboard Keys
Pause
Break
SysRq