Multi-touch technology is an advanced human-computer interaction technique that recogonises multiple touch points and also includes the hardware devices that implement it, which allow users to compute without conventional input devices . Multi-touch consists of a touch screen (screen, table, wall, etc.) or touchpad, as well as a software that recognizes multiple simultaneous touch points, as opposed to the standard touchscreen which recognizes only one touch point at a time.
Multi touch using Frustrated Total Internal Reflection is a simple, inexpensive, and scalable technique for enabling high-resolution multi- touch sensing on rear-projected interactive surfaces. Different applications for multi-touch interfaces both exist and are being proposed. Some uses are individualistic eg iPhone, iPod touch, MacBook Pro, MacBook Air. The use of multi-touch technology is expected to rapidly become common place.
A touch screen is a display which can detect the presence and location of a touch within the display area. The term generally refers to touch or contact to the display of the device by a finger or hand. Touch screens can also sense other passive objects, such as a stylus. However, if the object sensed is active, as with a light pen,