B YVINAYSHUKLA LAPTOPA laptop (notebook) is a personal computer f or mobile use. A lapt op i nt egrates most of the typical components of a desktop computer, including a displa y , a ke yboar d, a pointing de vice (a touchp ad, also known as a trackpad, and/or a poin ting stick) an d speakers int o a single unit. A laptop is powered by mains electri city via an AC adap ter , and can be used a way fr om an outlet using a rechargeable battery. Portable computers, originally monochrome CRT-based and developing into the modern laptop, were originally considered to be a small niche market, mostly for specialized field applications such as the military, accountants and sales representatives. As portable computers became smaller , lighter, and cheaper and as screens became larger and of better quality , laptops became very widely used for all sorts of purposes.
A laptop (notebook) is a personal computer for mobile use. A laptop integrates most of the typical components of a desktop computer, including a display, a keyboard, apointing device (a touchpad, also known as a trackpad, and/or a pointing stick) andspeakers into a single unit. A laptop is powered by mains electricity via an AC adapter,and can be used away from an outlet using a rechargeable battery.
Portable computers, originally monochrome CRT-based and developing into themodern laptop, were originally considered to be a small niche market, mostly forspecialized field applications such as the military, accountants and salesrepresentatives. As portable computers became smaller, lighter, and cheaper and asscreens became larger and of better quality, laptops became very widely used for allsorts of purposes.
As the personal computer became feasible in the early 1970s, theidea of a portable personal computer followed. A "personal, portableinformation manipulator" was imagined by Alan Kay at Xerox PARC in
1968, and described in his 1972 paper as the "Dynabook".
The IBM 5100, the first commercially available portable computer,appeared in September 1975, and was based on the SCAMPprototype. As 8-bit CPU machines became widely accepted, thenumber of portables increased rapidly. The Osborne 1, released in1981, used the Zilog Z80 and weighed 23.6 pounds (10.7 kg). It hadno battery, a 5 in (13 cm) CRT screen, and dual 5.25 in (13.3 cm)single-density floppy drives. In the same year the first laptop-sized
portable computer, the Epson HX-20, was announced. The Epsonhad a LCD screen, a rechargeable battery, and a calculator-sizeprinter in a 1.6 kg (3.5 lb) chassis
The first laptops using the flip form factor appeared in the early1980s. The Dulmont Magnum was released in Australia in
1981²82, but was not marketed internationally until 1984²85.The $8,150 ($18,540 in current dollar terms) GRiD Compass1100, released in 1982, was used at NASA and by the militaryamong others. The Gavilan SC, released in 1983, was the firstcomputer described as a "laptop" by its manufacturer From1983 onward, several new input techniques were developed andincluded in laptops, including the touchpad (Gavilan SC, 1983),
the pointing stick (IBM ThinkPad 700, 1992) and handwriting recognition (Linus Write-Top, 1987)
On March 2011, Lenovo has built the world's first eye-cotrolled
laptop with using eye tracking technology from Tobii. A built-insmall infrared camera will track eye's positioning which make asmouse do as select, point, scroll, etc. There are also games witheye fully functioning.
Portability is usually the first feature mentioned in any comparison of laptops versusdesktop PCs. Portability means that a laptop can be used in many places³not only athome and at the office, but also during commuting and flights, in coffee shops, inlecture halls and libraries, at clients' location or at a meeting room, etc. The portabilityfeature offers several distinct advantages:
Productivity: Using a laptop in places where a desktop PC can not be used, and attimes that would otherwise be wasted. For example, an office worker managing their
e-mails during an hour-long commute by train, or a student doing his/her homework atthe university coffee shop during a break between lectures.
Low power consumption: Laptops are several times more power-efficient thandesktops. A typical laptop uses 20²90 W, compared to 100²800 W for desktops. Thiscould be particularly beneficial for businesses (which run hundreds of personalcomputers, multiplying the potential savings) and homes where there is a computerrunning 24/7 (such as a home media server, print server, etc.)
All-in-One: designed to be portable, laptops have everything integrated in to the chassis.For desktops (excluding all-in-ones) this is divided into the desktop, keyboard, mouse,display, and optional peripherals such as speakers.
PerformanceWhile the performance of mainstream desktops and laptops is comparable, and the
cost of laptops has fallen more rapidly than desktops, laptops remain more expensivethan desktop PCs at the same performance level.
UpgradeabilityUpgradeability of laptops is very limited compared to desktops, which are thoroughlystandardized. In general, hard drives and memory can be upgraded easily. Optical
drives and internal expansion cards may be upgraded if they follow an industrystandard, but all other internal components, including the motherboard, CPU andgraphics, are not always intended to be upgradeable.
Ergonomics and healthBecause of their small and flat keyboard and trackpad pointing devices, prolonged useof laptops can cause repetitive strain injury.
The integrated screen often causes users to hunch over for a better view, which cancause neck or spinal injuries.
Security and privacyBecause they are valuable, common, and portable, laptops are prized targets for theft.
