A keyboard allows the user of a computer to input alphanumeric information and commands directly. Physical keyboards are most commonly operated by the user's hands while on-screen keyboards may be operated by voice, a mouse or other peripheral devices.
A keyboard maps a series of buttons on a matrix, each of which produces a designated response when activated. Depending on the technology employed, the activation of a button can be identified in a number of ways. A signal is then sent from the device to the computer through a cable or via wireless transmission where it is interpreted for use within general computing or a specific application.