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.
Tablets typically have other I/O capabilities that suit them to their usual tasks. These may include front-facing or rear-facing digital cameras, a microphone, GPS receiver, flashlight, magnetometer, proximity sensor, barometer, gyroscope and an accelerometer, so images on screens are displayed upright, or to sense velocity. Some have a fingerprint sensor, iris scanner, or face recognition. Most tablets use Wi-Fi, and some can also use cellular networks, for Internet access. Tablets can run various software known as apps; most basic apps (such as camera, photos, web browser, voice/video calls, emails, text messages, maps, weather, calendar, contacts, notes, app store, virtual assistant, etc.) come pre-installed with the system. Others may be installed online from the app store.
The touchscreen display uses gestures by finger or stylus to replace the mouse, trackpad and keyboard of larger computers. On the sides of the device, speakers, volume buttons (to control the sound emitted by the speakers), a headphone jack, and a USB port will be present. Devices may have a touchscreen home button (takes user to the starting user interface) at the bottom of the screen, or a physical home button or multiple buttons may be included below the touchscreen. Some tablets have a vibration feature, which may be used for a more vibrant experience in games, or for notifications. Tablets may be able to place and receive voice/video telephone calls using Voice over IP on Wi-Fi or cellular networks. Tablets largely resemble modern smartphones, the only differences being that tablets are relatively larger than smartphones, with screens 8 inches (20 cm) or larger, measured diagonally, and may not support access to a cellular network.
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 April 2010, Apple released the iPad, the first mass-market tablet to achieve widespread popularity. Thereafter in the 2010s, tablets rapidly rose in ubiquity and became a large product category used for personal, educational and workplace applications.