Some websites provides facility to play free online Games. Then do you know how to play free online Games ?
Most Online games are flash based. So you should have Flash software installed on your computer.
Then you should have speakers on your PC to hear sounds. Using your keyboard and mouse you can advance through different stages of a game.
Another factor to refer before you play free online games is the walkthrough and help of that peculiar game. This will guide you how to play that game.
Instructions supplied with the Help will provide you with shortcuts & navigation keys.