A mouse pad is a flat, smooth surface you place under a computer mouse to help it work better. Before optical and laser mice became common, computer mice had rubber balls on their undersides that rolled as you moved the mouse. These ball mice worked best on mouse pads because the pad's smooth, consistent surface helped the ball roll cleanly and accurately. Without a mouse pad, the ball might pick up dust and grime from a wooden desk or get confused by patterns in the wood grain, making the cursor jump around unpredictably on screen.

Modern optical mice use tiny cameras and lights instead of rolling balls, so they can work on most surfaces without needing a mouse pad. Many people still use mouse pads, though, because they create a designated workspace, protect the desk surface from wear, and feel more comfortable than sliding your mouse directly on a hard desk. Some mouse pads even have padded wrist rests attached to make long computer sessions more comfortable.

Gaming mouse pads can be quite large, giving players plenty of room for quick, sweeping mouse movements during intense gameplay.