Touchpad

A touchpad, also known as a trackpad, is a computer input device that allows a user to control a pointer on a graphical user interface (GUI) with a finger. It is a small, touch-sensitive surface typically found on laptop computers, but also available as a standalone peripheral device.

Touchpads operate by sensing the position and movement of a user's finger (or fingers) on the surface. Capacitive sensing is the most common technology used. The touchpad's surface consists of a grid of sensors that measure the capacitance changes caused by the presence of a finger. These changes are then translated into cursor movements on the screen.

Functionality typically includes basic cursor movement, scrolling, and clicking. Many touchpads also support multi-finger gestures, enabling users to perform actions such as zooming, rotating, and swiping. The specific gestures supported vary depending on the manufacturer and operating system.

Touchpads are generally more compact and integrated than other pointing devices like mice, making them well-suited for mobile computing. However, some users may prefer the precision and ergonomics of a mouse. Alternatives to touchpads include trackballs, pointing sticks, and touchscreens.