The space bar, spacebar, blank, or space key, is a key on a typewriter or alphanumeric keyboard in the form of a horizontal bar in the lowermost row, significantly wider than all other keys. Its main purpose is The space bar, also called the 'spacebar' or 'space key', is one of the most commonly used keys on a computer keyboard. It is it is at the bottom of most standard keyboard layouts, such as the QWERTY