Caffeine is a small program that prevent your PC from activating a screen saver or locking up. Caffeine will keep your PC awake, if it is locking up or going to sleep too often.
It works by simulating a keypress once every 59 seconds, so your machine thinks you are still working at the keyboard,Â so won’t lock the screen or activate the screensaver.
It sits on the system tray with an icon resembling a coffee pot. Double-clicking the icon empties the coffee pot and temporarily disables the program. Double-clicking it again refills the pot, and will keep your machine awake.