a program that displays a constantly shifting pattern on a screen when the computer is idle, originally used to prevent damage to the screen through continuous display of the same image but now used primarily for decoration.
Also screen·sav·er[skreen-sey-ver]/ˈskrinˌseɪ vər/
a computer program that reduces screen damage resulting from an unchanging display when a computer is switched on but not in use by blanking the screen or generating moving patterns, etc
