| A laptop computer or simply laptop (also notebook | | | | dimensions and longer battery life, although the length |
| computer or notebook) is a small mobile personal | | | | and width are usually determined by the screen size. |
| computer, usually weighing from one to three | | | | Desktop replacement computers |
| kilograms, depending on size, materials and other | | | | Powerful laptops meant to be mainly used in a fixed |
| factors.While the terms "laptop" and "notebook" are | | | | location and infrequently carried out due to their weight |
| often used interchangeably, "laptop" is the older term, | | | | and size; the latter provides more space for powerful |
| introduced in 1983 with the Gavilan SC. "Notebook | | | | components and a big screen, usually measuring 15 |
| computer" is a later coinage, which was used to | | | | inches or more. Desktop replacements tend to have |
| differentiate smaller devices such as those of the | | | | limited battery life, rarely exceeding three hours, |
| Compaq LTE series in 1989, which were, in contrast to | | | | because the hardware does not optimize power |
| previous laptops, the approximate size of an A4 paper | | | | efficiency. |
| sheet.[1] Either term is often used improperly: due to | | | | History |
| heat and other issues, many laptops are inappropriate | | | | Before laptop/notebook computers were technically |
| for use on one's lap, and most are not the size of an | | | | feasible, similar ideas had been proposed, most notably |
| A4 sheet. Although, some older portable computers, | | | | Alan Kay's Dynabook concept, developed at Xerox |
| such as the Macintosh Portable and certain Zenith | | | | PARC in the early 1970s.The first commercially |
| TurbosPort models, were sometimes described as | | | | available portable computer was the Osborne 1 in 1981, |
| "laptops", their size and weight were too great for this | | | | which used the CP/M operating system. Although it |
| category.Laptops usually run on a single battery or | | | | was large and heavy compared to today's laptops, |
| from an external AC/DC adapter which can charge | | | | with a tiny CRT monitor, it had a near-revolutionary |
| the battery while also supplying power to the | | | | impact on business, as professionals were able to take |
| computer itself.An Acer laptop with touchpadAs | | | | their computer and data with them for the first time. |
| personal computers, laptops are capable of the same | | | | This and other "luggables" were inspired by what was |
| tasks as a desktop PC, although they are typically less | | | | probably the first portable computer, the Xerox |
| powerful for the same price. They contain | | | | NoteTaker, again developed at Xerox PARC, in 1976; |
| components that are similar to their desktop | | | | however, only ten prototypes were built. The Osborne |
| counterparts and perform the same functions, but are | | | | was about the size of a portable sewing machine, and |
| miniaturized and optimized for mobile use and efficient | | | | importantly could be carried on a commercial aircraft. |
| power consumption. Laptops usually have liquid crystal | | | | However, it was not possible to run the Osborne on |
| displays and most of them use different memory | | | | batteries; it had to be plugged in.A more enduring |
| modules for their RAM (for instance, SO-DIMM in lieu | | | | success was the Compaq Portable, the first product |
| of the larger DIMMs). In addition to a built-in keyboard, | | | | from Compaq, introduced in 1983, by which time the |
| they may utilize a touchpad (also known as a | | | | IBM Personal Computer had become the standard |
| trackpad) or a pointing stick for input, though an | | | | platform. Although scarcely more portable than the |
| external keyboard or mouse can usually be | | | | Osborne machines, and also requiring AC power to |
| attached.Categories | | | | run, it ran MS-DOS and was the first true IBM clone |
| Terms sometimes used for subtypes of laptop | | | | (IBM's own later Portable Computer, which arrived in |
| computers include:Ultraportables | | | | 1984, was notably less IBM PC-compatible than the |
| Laptops with screens typically less than 12 inches | | | | Compaq[citation needed]).Another significant machine |
| diagonally and a weight of less than 1.7kg. Their | | | | announced in 1981, although first sold widely in 1983, |
| primary audience is usually business travellers, who | | | | was the Epson HX-20. A simple handheld computer, it |
| need small, light laptops. Ultraportables are often very | | | | featured a full-transit 68-key keyboard, rechargable |
| expensive and house power-saving CPUs and almost | | | | nickel-cadmium batteries, a small (120 x 32-pixel) |
| always have integrated graphics. | | | | dot-matrix LCD display with 4 lines of text, 20 |
| Thin-and-lights | | | | characters per line text mode, a 24 column dot matrix |
| Laptops usually weighing in between 1.8kg and 2.8kg | | | | printer, a Microsoft BASIC interpreter, and 16 kB of |
| with a screen size of between 12 and 14 inches | | | | RAM (expandable to 32 kB).However, arguably the |
| diagonally. | | | | first true laptop was the GRiD Compass 1101, designed |
| Medium-sized laptops | | | | by Bill Moggridge in 1979-1980, and released in 1982. |
| These usually have screens of 15 - 15.4 inches | | | | Enclosed in a magnesium case, it introduced the now |
| diagonally and a weight of around 3-3.5kg. They usually | | | | familiar clamshell design, in which the flat display folded |
| sacrifice a little computing power for smaller | | | | shut against the keyboard. |