A laptop computer, also known as a notebook computer, is a small personal computer designed for mobile use. A laptop integrates all of the typical components of a desktop computer, including a display, a keyboard, a pointing device (a touchpad, also known as a trackpad, or a pointing stick) and a battery into a single portable unit. The rechargeable battery is charged from an AC/DC adapter and has enough capacity to power the laptop for several hours.
A laptop is usually shaped like a large notebook with thickness of 0.7–1.5 inches (18–38 mm) and dimensions ranging from 10x8 inches (27x22cm, 13" display) to 15x11 inches (39x28cm, 17" display) and up. Modern laptops weigh 3 to 12 pounds (1.4 to 5.4 kg), and some older laptops were even heavier. Most laptops are designed in the flip form factor to protect the screen and the keyboard when closed.
Originally considered "a small niche market"[1] and perceived as suitable for "specialized field applications" such as "the military, the Internal Revenue Service, accountants and sales representatives"[1][2], battery-powered portables had just 2% worldwide market share in 1986[3]. But today, there are already more laptops than desktops in the enterprise[4] and, according to a forecast by Intel, more laptops than desktops will be sold in the general PC market as soon as 2009As the personal computer became feasible in the early 1970s, the idea of a portable personal computer followed; in particular, a "personal, portable information manipulator" was envisioned by Alan Kay at Xerox PARC in 1968[6] and described in his 1972 paper as the "Dynabook"[7].
The first commercially available portable computer appeared nine years later, in 1981. The Osborne 1 weighed 23.5 pounds (10.7 kg). It had no battery, a tiny 5" CRT screen and dual 5¼" single-density floppy drives. In the same year the first laptop-sized portable computer, the Epson HX-20, was announced[8]. The Epson had a LCD screen, a rechargeable battery and a calculator-size printer in a 1.6 kg (4 pounds) enclosure.
Wednesday, January 21, 2009
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