Pinch to zoom

In computing, multi-touch is technology that enables a surface (a trackpad or touchscreen) to recognize the presence of more than one or more than twopoints of contact with the surface. The origins of multitouch began at CERN, MIT, University of Toronto, Carnegie Mellon University and Bell Labs. The term "multi-touch" was popularized in 2007 by Apple, though it was in used as early as 1999. This plural-point awareness may be used to implement additional functionality, such as pinch to zoom or to activate certain subroutines attached to predefined gestures.

The two different uses of the term are the result of the quick developments in this field, which resulted in many companies using the term "multi-touch" for marketing purposes for older technology that is called gesture-enhanced single-touch or several other terms by other companies and researchers. There are several other similar or related terms that attempt to differentiate between whether a device can exactly determine or only approximate the location of different points of contact and that attempt to further differentiate between the various technological capabilities, but they are often used as synonyms in marketing.

The use of touchscreen technology to control electronic devices pre-dates multi-touch technology and the personal computer. Early synthesizer and electronic instrument builders like Hugh Le Caine and Robert Moog experimented with using touch-sensitive capacitance sensors to control the sounds made by their instruments.IBM began building the first touch screens in the late 1960s, and, in 1972, Control Data released the PLATO IV computer, a terminal used for educational purposes that employed single-touch points in a 16x16 array as its user interface.

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