A tablet computer, commonly shortened to tablet, is a portable PC, typically with a mobile operating system and LCD touchscreen display processing circuitry, and a rechargeable battery in a single thin, flat package. Tablets, being computers, do what other personal computers do, but lack some I/O capabilities that others have. Modern tablets largely resemble modern smartphones, the only differences being that tablets are relatively larger than smartphones, with screens 7 inches (18 cm) or larger, measured diagonally, and may not support access to a cellular network.
The touchscreen display uses gestures by finger or stylus instead of the mouse, trackpad and keyboard of larger computers. Portable computers can be classified according to the presence and physical appearance of keyboards. Slates and booklets do not have a physical keyboard, and usually accept text and other input by use of a virtual keyboard shown on a touchscreen-enabled display. Hybrids, convertibles, and 2-in-1s all have physical keyboards (although these are usually concealable or detachable), yet they typically also make use of virtual keyboards. Some 2-in-1s have processors and operating systems like a full laptop, whilst having the flexibility of being used as a tablet. Most tablets can use separate keyboards connected using Bluetooth.
The format was conceptualized in the mid-20th century (Stanley Kubrick depicted fictional tablets in the 1968 science fiction film 2001: A Space Odyssey) and prototyped and developed in the last two decades of that century. In 2010, Apple released the iPad, the first mass-market tablet to achieve widespread popularity. Thereafter tablets rapidly rose in ubiquity and briefly became a large product category used for personal, educational and workplace applications. From the mid-2010s, tablet computers started to decline, having been surpassed by both 2-in-1 hybrids and larger-sized smartphones.