screen saver
noun
,
Computers.
1.
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,
screensaver
[
skreen
-sey-ver]
/ˈskrinˌseɪ vər/
(
Show IPA
)
.