DPI (Dots Per Inch) is a measurement that indicates how sensitive a computer mouse is to movement. It refers to the number of individual dots the mouse sensor can detect within a one-inch space. A higher DPI means the cursor moves further on the screen with less physical movement, allowing for more precise and rapid control. This setting is especially important for activities like gaming or graphic design, where accuracy and speed are crucial. Adjusting DPI lets users customize the mouse's responsiveness to suit their preferences and tasks.