Thus you have a 0-1 property. To add touch to a computer screen you need four basic components. Monitor on which the sensor can be fitted. Controller which enables the sensor to work like any other peripheral Software Driver which allows the controller and the computer-operating system to communicate and helps the controller recognize input. One technology to create a touch screen is by adding a capacitive conductive coating to a clear glass sensor.
Voltage is applied to the corners.
When the screen is not in use the voltage is spread out into a uniform field. When the field is touched by a finger, the X-Y position is recognized by the disturbance in the field. A second technology is a resistive touchscreen which conducts electricity when touched and the position where touched can be calculated. The use of touchscreens in point of sale, POS, devices can speed up the transaction process and reduce employee training time. People who are computer illiterate find touchscreens easier to use than keyboards.