A space bar, also called the 'spacebar' or 'space key', is a key on a keyboard. It can be found at the bottom of most keyboards. The space bar is wider than all of the other keys on the keyboard. This key adds a space in between words, for example when typing. On many computers, you can press the space bar with the alt key or control key to activate many useful functions, such as minimizing windows. In most web browsers, you can scroll down by pressing the space key.