Alaptopor anotebookis a portablepersonal computerwith aclamshellform factor, suitable formobile use.[1]There was a difference between laptops and notebooks in the past, but nowadays it has gradually died away.[2]Laptops are commonly used in a variety of settings, including at work, in education, and for personal multimedia.A laptop combines the components and inputs of a desktop computer, includingdisplay,speakers,keyboardand pointing device (such as atouchpador a trackpad) into a single device. Most modern-day laptops also have an integratedwebcamand amicrophone. A laptop can be powered either from arechargeable battery, or bymains electricityvia anAC adapter. Laptop is a diverse category of devices and other more specific terms, such asrugged notebookorconvertible, refer to specialist types of laptops, which have been optimized for specific uses. Hardware specifications change significantly between different types, makes and models of laptops.Portable computers, which later developed into modern laptops, were originally considered to be a small niche market, mostly for specialized field applications, such as the military, accountancy, for sales representatives etc. As portable computers developed and became more like modern laptops, becoming smaller, lighter, cheaper, and more powerful, they became very widely used for a variety of purposes.As the personal computer (PC) became feasible in 1971, the idea of a portable personal computer followed. A "personal, portable information manipulator" was imagined byAlan KayatXerox PARCin 1968,[6]and described in his 1972 paper as the "Dynabook".[7]The IBM Special Computer APL Machine Portable (SCAMP), was demonstrated in 1973. This prototype was based on theIBM PALM processor(Put All Logic in Microcode or 128 bit).[8]TheIBM 5100, the first commercially available portable computer, appeared in September 1975, and was based on the SCAMP prototype.[9]As 8-bit CPU machines became widely accepted, the number of portables increased rapidly. TheOsborne 1, released in 1981, used the Zilog Z80 and weighed 23.6 pounds (10.7kg). It had no battery, a 5in (13cm)CRTscreen, and dual 5.25in (13.3cm) single-density floppy drives. In the same year the first laptop-sized portable computer, theEpson HX-20, was announced.[10]The Epson had aLCDscreen, a rechargeable battery, and a calculator-size printer in a 1.6kg (3.5lb) chassis. BothTandy/RadioShackandHPalso produced portable computers of varying designs during this period.[11][12]The first laptops using theflip form factorappeared in the early 1980s. TheDulmont Magnumwas released in Australia in 198182, but was not marketed internationally until 198485. The US$8,150 (US$19,920 today)GRiD Compass 1100, released in 1982, was used atNASAand by the military among others. TheGavilan SC, released in 1983, was the first computer described as a "laptop" by its manufacturer.[13]From 1983 onward, several new input techniques were developed and included in laptops, including thetouchpad(Gavilan SC, 1983), thepointing stick(IBMThinkPad700, 1992) and handwriting recognition (Linus Write-Top,[14]1987). Some CPUs, such as the 1990 Inteli386SL, were designed to use minimum power to increase battery life of portable computers, and were supported by dynamic power management features such as IntelSpeedStepand AMDPowerNow!in some designs.