A
tablet computer, or a
tablet, is a
mobile computer, larger than a mobile phone or
personal digital assistant, integrated into a flat
touch screen and primarily operated by touching the screen rather than using a physical
keyboard. It often uses an onscreen
virtual keyboard, a passive
stylus pen, or a
digital pen.
[1][2][3] The term may also apply to a variety of
form factors that differ in position of the screen with respect to a keyboard. The standard form of tablet does not have an integrated keyboard but may be connected to one with a
wireless link or a
USB port.
Convertible notebook computers have an integrated keyboard that can be hidden by a
swivel joint or
slide joint, exposing only the screen for touch operation.
Hybrids have a detachable keyboard so that the touch screen can be used as a stand-alone tablet.
Booklets include
dual-touchscreens, and can be used as a notebook by displaying a virtual keyboard in one of them.
Early examples of the
information tablet concept originated in the 19th and 20th centuries mainly as prototypes and concept ideas; prominently,
Alan Kay's
Dynabook of 1968. The first commercial portable electronic devices based on the concept appeared at the end of the 20th century. During the 2000s Microsoft attempted a relatively unsuccessful product line with
Microsoft Tablet PC, which carved a niche market at hospitals and outdoor businesses.