trackpads

A trackpad, or touchpad, is a flat input device that detects finger position and movement on its surface. It is widely used as the primary pointing device on laptops and is available as external devices for desktops.

Most modern trackpads use capacitive sensing: a grid of electrodes beneath the surface detects changes in capacitance as a finger approaches or touches. This enables precise tracking and multi-touch input. Some models add force sensing (pressure) for extra actions; older or specialized pads may use other sensing methods, but capacitive sensing is standard today.

Clicking is usually done by tapping, pressing in a designated area, or by a separate physical button (or an integrated click mechanism). Many pads provide haptic feedback or an audible click. Palm rejection helps prevent accidental input when typing.

Gestures are a major feature: two-finger scrolling, pinch-to-zoom, and three- or four-finger swipes for switching apps or desktops. These gestures are configurable in the operating system. Driver support varies: Windows uses Precision drivers; macOS uses its own system; Linux commonly relies on libinput or vendor utilities.

Form factors range from compact external pads to large laptop pads. Some manufacturers use buttonless designs with integrated click regions or Force Touch haptic mechanisms. Trackpads are valued for quiet operation, space efficiency, and support for complex gestures, though some users prefer mice for certain tasks.