There are two major categories of touch screen displays. These are Capacitive Touch screen and Resistive Touchscreen.

There are two major categories of touch screen displays. These are Capacitive Touch screen and Resistive Touchscreen.

Capacitive Touch screen Display rely on the electrical properties of the human body to detected when and where on the screen the user touches. Because of this, Capacitive display can be controlled with very light touches of a finger and generally can not be used with mechanical stylus or a gloved hand.

Resistive Touchscreen - Display are composed of multiple layers that are separated by thin space. Pressure applied to the surface of the display by a finger or stylus causes the layer to touch, which complete electrical circuits and tells the device where the user is touching.

Compare of Touch screen

Capacitive Touch screen.

Cost - High cost as compared to Resistive touchscreen
Accuracy - Capacitive Touch screen tend to be less accurate, but more responsive than Resistive
Multi-Touch - Mutli- touch capabilities, which can recognize multiple simultaneous Finger touches, allowing for enhanced manipulation of non screen objects.
Visibility - Visible good even in sun light.

Resistive Touch screen.

Cost - Lower Cost
Accuracy - Resistive touch screens are passive and can respond to any kind of pressure on the screen.
Multi-Touch - limited possibility of multi touch on a Resistive touchscreen.
Visibility - Visibility is not good in sun light.