Touch screens are very popular in commercial set-ups like restaurants, airports, ATMs, industrial automation, and in computer-based training. In restaurants, customers use touch screens as ordering points where they can place their order on their own without dealing with a retail clerk. In computer-based learning, a touch screen is very helpful especially since it keeps the learner focused on the display and learners do not need any technical know-how to operate the keyboard or hardware.
Touch screen systems are either in the form of touch screen add-ons or touch screen monitors. The touch screen add-on technology is most useful when the touch screen is an upgrade to an existing display system. Commonly, an add-on touch sensitive peripheral is placed in front of an ordinary computer display unit. A controller is connected to the overlay and the PC. This controller communicates between the PC, the display, and the monitor. The other kind of touch screen display is the touch screen monitor.