A screensaver displays moving images on your screen when your computer is not being used. Screensavers also help prevent older monitors being damaged by the same image being displayed for long periods of time. To stop the screensaver and return to the desktop, move the mouse or press a key on the keyboard.
Use the Screensaver preference tool to set the type of screensaver, the time before the screensaver starts, and whether to require a password to return to the desktop.
You can modify the following settings:
Select the Screensaver theme from the list. A reduced version of the selected screensaver theme is shown. Press Preview to show the selected theme on the whole screen. During preview, use the arrow buttons at the top of the screen to go through the list of screensaver themes.
Which screensavers are shown in the remainder of the list depends on your distributor or vendor.
Your computer becomes idle after this amount of time has passed with no input from you, such as moving the mouse or typing. This may affect power management (the monitor may power down for example) or instant messaging (chat applications may set your status as "away"). Use the slider to set the length of time in minutes or hours.
Select this option to have the screensaver start after the set length of time.
When this option is selected, the screensaver will prompt you for your password when you try to return to the desktop. For more on locking your screen, see Section 3.2 ― Locking Your Screen.