What Does Multitouch Mean?
Multitouch refers to the ability of a touch-sensing surface (usually a touch screen or a trackpad) to detect or sense input from two or more points of contact simultaneously. Multitouch sensing is made possible by the presence of an application-specific integrated circuit (ASIC) sensor, which is attached to the touch surface.
Multitouch functionality enables users to perform multiple finger gestures, such as pinching the screen for zooming in, or spreading the screen for zooming out. Multitouch also enables wiping and rotating, which offers enhanced user and virtual object interaction.
The earliest touchscreens were built with single touch detection. Today's most popular smartphones and tablets have multiple touch detection capability.
Techopedia Explains Multitouch
Prior to the introduction of multitouch technology, a user would press a real or virtual button to zoom into a document or image. With multitouch, a user achieves the same effect with specific finger gestures. Similarly, in the past, object rotation required a user to press a virtual button, usually symbolized by a two-triangle icon. Using multitouch screens, a user may achieve the same effect with clockwise or counter-clockwise finger gestures.
Multitouch technology is mostly used in smartphones, but larger devices also support such interfaces. Tablet PCs like the Apple iPad, and touchables like the Microsoft Surface are examples of such devices. Some laptop trackpads, such as the MacBook Pro version, also support multitouch gestures.
To meet the demand for multitouch device capability, more operating systems provide integrated interface support. Desktop operating systems, such as Mac OS X, Windows 7 and Ubuntu, as well as mobile operating systems, including iOS, Android and Symbian^3, already support multitouch detection.