Do I need a screensaver?

If you have an older CRT-type monitor, then yes. If you have a newer flat panel (a.k.a. TFT or LCD) then no, although you still shouldn't keep it on all the time.

CRT (Cathode Ray Tube) monitors are traditional computer monitors that are mechanically very similar to televisions. Due to the high energy of some of the radiation emitted from CRTs, if they are left displaying the same image for long periods of time, they can "burn" the image into the glass of the display, leaving a (permanent) ghostly afterimage. For this reason, we have screensavers, which display various moving images on your screen after you're left it alone for a few minutes. Since the images are always moving, screen burn is avoided.

Newer, flat panel monitors don't give off this kind of high-energy radiation (they just use a flourescent backlight). For this reason, you don't have to worry about screen burn. However, this doesn't mean that you can just leave your monitor on all the time. For one thing, it wastes power, and for another you will be using up the lifetime of your flourescent backlight faster than normal (they tend to dim over time).

You can set your monitor to automatically turn off after a certain period of time by going to Start > Control Panel > Power Options.

How do I change my screen saver?

PC

Right-click on your desktop and select Properties from the menu that appears. The "Display Properties" window should appear. Click on the Screen Saver tab and select the screensaver you want from the list (you can also set the delay time before it activates).

Mac

Control Click on your desktop and select Change Desktop Background... from the menu that appears. The "Desktop & Screen Saver" window will appear. Click on the Screen Saver tab and select the screensaver you want from the list (you can also set the delay time before it activates).

Where can I get other screensavers?

Windows comes with a fair amount of screensavers, but the internet offers many more options.

WARNING: "Installed" screensavers are a popular way for spyware and other adware to creep into your machine. All you need to do to install a screensaver is place its .scr file (this should be provided) into your C:\Windows\System32 folder. This file should always be provided. You should never have to use an "installer" program to install a screensaver. If something claims that you need to, it's probably trying to install a bunch of over nasty spyware/adware along with it.

Here are two sites with reputable screen savers (though by no means the only ones):

• Really Slick Screensavers
• Wincustomize