Caffeine for Mac is a great utility for preventing the computer from starting its screensaver, going to sleep, or automatically dimming its screen after a period of inactivity. It's like serving your computer a cup of coffee, so that it remains awake, just like the user does while watching a movie or reading a document. Caffeine is very simple to activate: just click on the coffee icon on the Menu bar to enable it and then click again to disable it.
Before this virtual caffeine for Mac computers was invented, users needed to access System Preferences and go to the Energy Saver panel to turn off automatic screen dimming and other options if they wanted to keep the computer awake for a while. And then they had to reverse the procedure when they finished whatever they were doing in order to restore the computer to its normal operating parameters. Caffeine solves this issue by providing a one-click interaction in the Menu bar, and has several very handy custom options.
For instance, you can set the time frame during which you need the "caffeinated" computer, from 5 minutes to indefinitely. We must note here that the normal parameters of the Energy Saver panel won't be affected, yet the computer remains awake while you need it. However, don't expect this nifty app to prevent the computer from getting sleepy when you close it; there are other apps to prevent that.
Caffeine excels at what it is designed to do, and we found it useful during presentations. It could be a helpful tool for any Mac user who does things that require a temporarily insomniac computer.