Have you ever opened up your computer and had a look inside the case? No need to do it now, but you will find that it is built from a number of parts necessary to deliver your computing experience. The video card generates an image and sends a signal to your monitor. The sound card mixes sound together and sends audio to your speakers. Then there are the input devices, such as the keyboard, mouse, and joystick(s), and a variety of other electronic gizmos—all of which are essential in making a game.