What is a purpose of a screensaver?

Answer 1

Back in the day, older CRT monitors had a problem with memory-effect -- if you left an image or text in the same position on the screen long enough, it would "burn into" the screen. Even if you turned the monitor off, you could still see the burned-in images.

To prevent this, screen savers change the display on a more or less random basis.

It's not as great a problem with LCD monitors, but a better solution exists -- use the power-saver option of the monitor to shut the screen down when it's not in use. Not only does this preserve the screen, it also saves energy and money.

Answer 2

Computer screen savers used to server the purpose of preventing your CRT monitor from "etching" where the image of your desktop (or your prompt - in the days before Macs and Windows operating systems) would stay on your screen as a sort of ghost image when you went into another program. Now days, the Computer Monitors do not etch, so screen servers really only serve the purpose of entertainment. Dispite the fact that they no longer save anything (except for possibly power, if your screen goes black) they have maintained their original software classification.
it saves the energy of your computer -_-

Answer 3

They have no actual use nowadays, but back when computers with CRT screens first came out, they had 'burn in' problems. What would happen is the screens back then used a more powerful ion beam, and would burn holes in the screen if left too long. The purpose of the screen saver was to quite literally save your screen from holes.

Answer 4

I think it saves your screen from having an image burnt into it.