Laptop

A laptop computer or notebook computer, also known as a laptop or notebook, is a small, portable personal computer (PC). Laptops typically have a clamshell form factor with a flat-panel screen on the inside of the upper lid and an alphanumeric keyboard and pointing device on the inside of the lower lid. Most of the computer's internal hardware is in the lower part, under the keyboard, although many modern laptops have a built-in webcam at the top of the screen, and some even feature a touchscreen display. In most cases, unlike tablet computers which run on mobile operating systems, laptops tend to run on desktop operating systems, which were originally developed for desktop computers.

Laptops are used in a variety of settings, such as at work (especially on business trips), in education, for playing games, content creating, web browsing, for personal multimedia, and for general home computer use. They can run on both AC power and built-in rechargable batteries, and can be folded shut for convenient storage and transportation, making them suitable for mobile use. Laptops combine essentially the same input/output components and capabilities of a desktop computer into a single unit, including a display screen (usually 11–17 in or 280–430 mm in diagonal size), small speakers, a keyboard, and a pointing device (usually touchpads). Hardware specifications may vary significantly between different types, models, and price points.

Design elements, form factors, and construction can also vary significantly between models depending on the intended use. Examples of specialized models of laptops include 2-in-1 laptops, with keyboards that either be detached or pivoted out of view from the display (often marketed having a "laptop mode"), and rugged laptops, for use in construction or military applications. Portable computers, which later developed into modern laptops, were originally considered to be a small niche market, mostly for specialized field applications, such as in the military, for accountants, or travelling sales representatives. As portable computers evolved into modern laptops, they became widely used for a variety of purposes.

The history of the laptop follows closely behind the development of the personal computer itself. A "personal, portable information manipulator" was imagined by Alan Kay at Xerox PARC in 1968, and described in his 1972 paper as the "Dynabook". The IBM Special Computer APL Machine Portable (SCAMP) was demonstrated in 1973. This prototype was based on the IBM PALM processor. The IBM 5100, the first commercially available portable computer, appeared in September 1975, and was based on the SCAMP prototype.

As 8-bit CPU machines became widely accepted, the number of portables increased rapidly. The first "laptop-sized notebook computer" was the Epson HX-20, invented (patented) by Suwa Seikosha's Yukio Yokozawa in July 1980, introduced at the COMDEX computer show in Las Vegas by Japanese company Seiko Epson in 1981, and released in July 1982. It had an LCD screen, a rechargeable battery, and a calculator-size printer, in a 1.6 kg (3.5 lb) chassis, the size of an A4 notebook. It was described as a "laptop" and "notebook" computer in its patent.

Both Tandy/RadioShack and Hewlett-Packard (HP) also produced portable computers of varying designs during this period. The first laptops using the flip form factor appeared in the early 1980s. The Dulmont Magnum was released in Australia in 1981–82, but was not marketed internationally until 1984–85. The US$8,150 (equivalent to $26,550 in 2024) GRiD Compass 1101, released in 1982, was used at NASA and by the military, among others. The Sharp PC-5000, the Ampere WS-1, and Gavilan SC were released between 1983 and 1985. The Toshiba T1100 won acceptance by PC experts and the mass market as a way to have PC portability.

From 1983 onward, several new input techniques were developed and included in laptops, including the touch pad (Gavilan SC, 1983), the pointing stick (IBM ThinkPad 700, 1992), and handwriting recognition (Linus Write-Top, 1987). Some CPUs, such as the 1990 Intel i386SL, were designed to use minimum power to increase the battery life of portable computers and were supported by dynamic power management features such as Intel SpeedStep and AMD PowerNow! in some designs.

Some laptops in the 1980s using red plasma displays could only be used when connected to AC power, and had a built in power supply.