<P> A touchpad or trackpad is a pointing device featuring a tactile sensor, a specialized surface that can translate the motion and position of a user's fingers to a relative position on the operating system that is made output to the screen . Touchpads are a common feature of laptop computers, and are also used as a substitute for a mouse where desk space is scarce . Because they vary in size, they can also be found on personal digital assistants (PDAs) and some portable media players . Wireless touchpads are also available as detached accessories . </P> <P> Touchpads operate in one of several ways, including capacitive sensing and resistive touchscreen . The most common technology used as of 2010 entails sensing the capacitive virtual ground effect of a finger, or the capacitance between sensors . Capacitance - based touchpads will not sense the tip of a pencil or other similar implement . Gloved fingers may also be problematic . </P>

What is a track pad on a laptop