Once a screen saver is chosen, Windows monitors keystrokes and mouse movements and then starts the screen saver after a period of inactivity.

Screen savers are loaded automatically when Windows starts or when a user activates the screen saver through the Control Panel. The Desktop application in the Windows Control Panel lets users select from a list of screen savers, specify how much time should elapse before the screen saver starts, configure screen savers, and preview screen savers.

This topic is divided into the following sections. Screen savers start when the mouse and keyboard have been idle for a specified period of time. The Microsoft Win32 API supports special applications called screen savers.