Space bar
key on a typewriter or alphanumeric keyboard in the form of a horizontal bar
The space bar, also called the 'spacebar' or 'space key', is one of the most commonly used keys on a computer keyboard. It is used to put a space into something being typed. It is at the bottom of most standard keyboard layouts, such as the QWERTY keyboard. The space bar is wider than all of the other keys on the keyboard.
On many computers, pressing the space bar at the same time as the ALT or CTRL key can activate many useful functions. For example, it can minimize a window in some operating systems. In some web browsers, pressing the space bar makes a window scroll down.