Before laptop/notebook computers were technically feasible, similar ideas had been proposed, most notably Alan Kay's Dynabook concept, developed at Xerox PARC in the early 1970s.

The first commercially available portable computer was the Osborne 1 in 1981, which used the CP/M operating system. Although it was large and heavy compared to today's laptops, with a tiny CRT monitor, it had a near-revolutionary impact on business, as professionals were able to take their computer and data with them for the first time. This and other "luggables" were inspired by what was probably the first portable computer, the Xerox NoteTaker, again developed at Xerox PARC, in 1976; however, only ten prototypes were built. The Osborne was about the size of a portable sewing machine, and importantly could be carried on a commercial aircraft. However, it was not possible to run the Osborne on batteries: it had to be plugged into mains.

In 1982 Kaypro introduced the Kaypro II, a CP/M-based competitor to the Osborne 1. The Kaypro II featured a display nearly twice as big as the Osborne's and double-sided floppy drives with twice the storage capacity.

A more enduring success was the Compaq Portable, the first product from Compaq, introduced in 1983, by which time the IBM Personal Computer had become the standard platform. Although scarcely more portable than the Osborne machines, and also requiring AC power to run, it ran MS-DOS and was the first true IBM clone (IBM's own later Portable Computer, which arrived in 1984, was notably less IBM PC-compatible than the Compaq[citation needed]).

Another significant machine announced in 1981, although first sold widely in 1983, was the Epson HX-20. A simple handheld computer, it featured a full-transit 68-key keyboard, rechargeable nickel-cadmium batteries, a small (120 x 32-pixel) dot-matrix LCD display with 4 lines of text, 20 characters per line text mode, a 24 column dot matrix printer, a Microsoft BASIC interpreter, and 16 KB of RAM (expandable to 32 KB).

However, arguably the first true laptop was the GRiD Compass 1101, designed by Bill Moggridge in 1979-1980, and released in 1982. Enclosed in a magnesium case, it introduced the now familiar clamshell design, in which the flat display folded shut against the keyboard. The computer could be run from batteries, and was equipped with a 320×200-pixel plasma display and 384 kibibyte bubble memory. It was not IBM-compatible, and its high price (US$8,000–10,000) limited it to specialized applications. However, it was used heavily by the U.S. military, and by NASA on the Space Shuttle during the 1980s. The GRiD's manufacturer subsequently earned significant returns on its patent rights as its innovations became commonplace. GRiD Systems Corp. was later bought by the Tandy (now RadioShack) Corporation.

Two other noteworthy early laptops were the Sharp PC-5000 and the Gavilan SC, announced in 1983 but first sold in 1984. The Gavilan was notably the first computer to be marketed as a "laptop". It was also equipped with a pioneering touchpad-like pointing device, installed on a panel above the keyboard. Like the GRiD Compass, the Gavilan and the Sharp were housed in clamshell cases, but they were partly IBM-compatible, although primarily running their own system software. Both had LCD displays, and could connect to optional external printers. The Dulmont Magnum, launched internationally in 1984, was an Australian portable similar in layout to the Gavilan, which used the Intel 80186 processor.[1]

The year 1983 also saw the launch of what was probably the biggest-selling early laptop, the Kyocera Kyotronic 85, which owed much to the design of the previous Epson HX-20. Although it was at first a slow seller in Japan, it was quickly licensed by Tandy Corporation, Olivetti, and NEC, which saw its potential and marketed it respectively as TRS-80 Model 100 line (or Tandy 100), Olivetti M-10, NEC PC-8201.[2] The machines ran on standard AA batteries. The Tandy's built-in programs, including a BASIC interpreter, a text editor, and a terminal program, were supplied by Microsoft, and are thought to have been written in part by Bill Gates himself. The computer was not a clamshell, but provided a tiltable 8×40-character LCD screen above a full-travel keyboard. With its internal modem, it was a highly portable communications terminal. Due to its portability, good battery life (and ease of replacement), reliability (it had no moving parts), and low price (as little as US$300), the model was highly regarded, becoming a favorite among journalists. It weighed less than 2 kg with dimensions of 30×21.5×4.5 centimeters (12×8½×1¾ in). Initial specifications included 8 kilobytes of RAM (expandable to 24 KB) and a 3 MHz processor. The machine was in fact about the size of a paper notebook, but the term had yet to come into use and it was generally described as a "portable" computer.

Possibly the first commercial IBM-compatible laptop was the Kaypro 2000, introduced in 1985. With its brushed aluminum clamshell case, it was remarkably similar in design to modern laptops. It featured a 25 line by 80 character LCD display, a detachable keyboard, and a pop-up 90 mm (3.5 inch) floppy drive.

Also among the first commercial IBM-compatible laptops were the IBM PC Convertible, introduced in 1986, and two Toshiba models, the T1000 and T1200, introduced in 1987. Although limited floppy-based DOS machines, with the operating system stored in read-only memory, the Toshiba models were small and light enough to be carried in a backpack, and could be run off lead-acid batteries. These also introduced the now-standard "resume" feature to DOS-based machines: the computer could be paused between sessions, without having to be restarted each time.

The first laptops successful on a large scale came in large part due to a Request For Proposal (RFP) by the U.S. Air Force in 1987. This contract would eventually lead to the purchase of over 200,000 laptops. Competition to supply this contract was fiercely contested and the major PC companies of the time; IBM, Toshiba, Compaq, NEC, and Zenith Data Systems (ZDS), rushed to develop laptops in an attempt to win this deal. ZDS, which had earlier won a landmark deal with the IRS for its Z-171, was awarded this contract for its SupersPort series. The SupersPort series was originally launched with an Intel 8086 processor, dual floppy disk drives, a backlit, blue and white STN LCD screen, and a NiCD battery pack. Later models featured an Intel 80286 processor and a 20 MB hard disk drive. On the strength of this deal, ZDS became the world's largest laptop supplier in 1987 and 1988. ZDS partnered with Tottori Sanyo in the design and manufacturing of these laptops. This relationship is notable because it was the first deal between a major brand and an Asian original equipment manufacturer.

Another notable computer was the Cambridge Z88, designed by Clive Sinclair, introduced in 1988. About the size of an A4 sheet of paper as well, it ran on standard batteries, and contained basic spreadsheet, word processing, and communications programs. It anticipated the future miniaturization of the portable computer; and, as a ROM-based machine with a small display, can—like the TRS-80 Model 100—also be seen as a forerunner of the personal digital assistant.

By the end of the 1980s, laptop computers were becoming popular among business people. The NEC UltraLite, released in mid-1989, was perhaps the first notebook computer, weighing just over 2 kg; in lieu of a floppy or hard drive, it contained a 2 mebibyte RAM drive, but this reduced its utility as well as its size. The first notebook computers to include hard drives were those of the Compaq LTE series, introduced toward the end of that year. Truly the size of a notebook, they also featured grayscale backlit displays with CGA resolution.