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.
Keyboard Lock Keys
Common Keyboard Keys
Not-so-Common Keyboard Keys