History

The Epson HX-20

As the personal computer became feasible in the early 1970s, the idea of a portable personal computer followed. 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 SCAMP project (Special Computer APL Machine Portable), was demonstrated in 1973. This prototype was based on the PALM processor (Put All Logic In Microcode).

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 Osborne 1, released in 1981, used the Zilog Z80 and weighed 23.5 pounds (10.7 kg). It had no battery, a 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. The Epson had a LCD screen, a rechargeable battery and a calculator-size printer in a 1.6 kg (3.5 lb) chassis. Both Tandy/RadioShack and HP also produced portable computers of varying designs during this period.

The first laptop using the flip form factor appeared in 1982. The $8150 GRiD Compass 1100 was used at NASA and by the military among others. The Gavilan SC, released in 1983, was the first notebook marketed using the term "laptop". From 1983 onwards, several new input techniques were developed and included in laptops, including the touchpad (Gavilan SC, 1983), the pointing stick (IBM ThinkPad 700, 1992) and handwriting recognition (Linus Write-Top, 1987). Some CPUs were designed specifically for low power use including laptops (Intel i386SL, 1990), and were supported by dynamic power management features (Intel SpeedStep and AMD PowerNow!) in some designs. Displays reached VGA resolution by 1988 (Compaq SLT/286) and 256-color screens by 1993 (PowerBook 165c), progressing quickly to millions of colors and high resolutions. High-capacity hard drives and optical storage (CD-ROM followed CD-R and CD-RW and eventually by DVD-ROM and the writable varieties) became available in laptops soon after their introduction to the desktops.

Classification

The general terms "laptop" or "notebook" can be used to refer to a number of classes of small portable computers:^[10][11]

By purpose and (approximately) by screen size: Desktop replacement – emphasizes performance, is less portable, 15" and larger screen; Standard laptop – balances portability and features, 13-15" screen; Subnotebook – emphasizes portability, has fewer features, 13" or smaller screen.

By features: Budget – a cheap, lower-performance standard-sized laptop; Tablet PC – Has a touch-screen interface, may or may not have a keyboard; Netbook – A cheaper, smaller version of a subnotebook suited to Internet surfing and basic office applications. Usually has a 9" screen. Gaming laptop - A larger laptop with a powerful graphics card for playing graphics-intensive computer games. Rugged – Engineered to operate in tough conditions (strong vibrations, extreme temperatures, wet and dusty environments).

Desktop Replacement

Dell XPS M140 Laptop.

Main article: Desktop replacement computer

A desktop replacement computer is a laptop that provides most of the capabilities of a desktop computer, with a similar level of performance. Desktop replacements are usually larger and heavier than standard laptops. They contain more powerful components and have a 15" or larger display.^[11] Because of their bulk, they are not as portable as other laptops and their operation time on batteries is typically shorter; instead, they are meant to be used as a more compact, easier to carry alternative to a desktop computer.^[11]

Some laptops in this class use a limited range of desktop components to provide better performance for the same price at the expense of battery life; in a few of those models, there is no battery at all and the laptop can only be used when plugged in. These are sometimes called desknotes, a portmanteau of the words "desktop" and "notebook," though the term can also be applied to desktop replacement computers in general.^[12]

In the early 2000s, desktops were more powerful, easier to upgrade, and much cheaper in comparison with laptops. But in the last few years, the advantages have drastically changed or shrunk since the performance of laptops has markedly increased.^[13] In the second half of 2008, laptops have finally outsold desktops for the first time ever. In the U.S., the PC shipment declined 10 percent in the fourth quarter of 2008. In Asia, the worst PC shipment growth went up 1.8 percent over the same quarter the previous year since PC statistics research started.^[14]

The names "Media Center Laptops" and "Gaming Laptops" are also used to describe specialized members of this class of notebooks.^[10]

Subnotebook

Sony VAIO C1 subnotebook.

Main article: Subnotebook

A subnotebook, also called an ultraportable by some vendors, is a laptop designed and marketed with an emphasis on portability (small size, low weight and long battery life) that retains the performance of a standard notebook. Subnotebooks are usually smaller and lighter than standard laptops, weighing between 0.8 and 2 kg (2 to 5 pounds); the battery life can exceed 10 hours when a large battery or an additional battery pack is installed.

To achieve the size and weight reductions, ultraportables use high resolution 13" and smaller screens (down to 6.4"), have relatively few ports, employ expensive components designed for minimal size and best power efficiency, and utilize advanced materials and construction methods. Some subnotebooks achieve a further portability improvement by omitting an optical/removable media drive; in this case they may be paired with a docking station that contains the drive and optionally more ports or an additional battery.

The term "subnotebook" is usually reserved to laptops that run general-purpose desktop operating systems such as Windows, Linux or Mac OS X, rather than specialized software such as Windows CE, Palm OS or Internet Tablet OS.

Netbook

An Asus Eee PC netbook.

Main article: Netbook

Netbooks are laptops that are light-weight, economical, energy-efficient and especially suited for wireless communication and Internet access. Hence the name netbook (as "the device excels in web-based computing performance") rather than notebook which pertains to size.

Especially suited for web browsing and e-mailing, netbooks "rely heavily on the Internet for remote access to web-based applications". and are targeted increasingly at cloud computing users who rely on servers and require a less powerful client computer. While the devices range in size from below 5 inches to over 12, most are between 7 and 11 inches and weigh between 2 and 3 pounds.

Netbooks normally use light-weight operating systems including Linux and Windows XP rather than more resource-intensive operating systems like Windows Vista, as they have less processing power than traditional laptops.

Recently Google has developed its own Chrome operating system for this market.