A History of Portable Computing

To further my series on the ThinkPad’s 25th anniversary, I’ll be discussing the history of portable computing and the role that the ThinkPad plays in the topic.


In comparison to bigger, more powerful mainframe and miniframe systems, microcomputers were considered “portable” for their time machine. However, they’re hardly portable by today’s computing standards. This meant that they could be easily moved from one location to another without having to tear into walls and floors, as well as not having to worry about shutting off power to entire rooms.

Microcomputer Mania! occurred in 1977, and saw the introduction of multiple microcomputers, including the Apple II, Commodore PET, and others. In 1981, IBM introduced the original Personal Computer (PC.)

Luggables and “not-so-laptop” Portables

CP/M-based Portables (Osborne and Kaypro)

Before the PC and MS-DOS, Digital Research’s CP/M dominated the market as an operating system. Thus, portable computers running CP/M were released well before PC portables.

The Osborne was released in April 1981 and featured a small display, two 5.25″ floppy drives, and a full-keyboard. The machine was powered by a Zilog Z80, and was a fairly successful portable for its time.

Kaypro II – 1981

A Kaypro II [source: Autopilot, wikipedia]
The Kaypro II, on the other hand, may have been the more popular choice. The Kaypro Corporation was founded by Andrew Kay in 1952 as Non-Linear Systems, who produced electronic test equipment. This included the first digital voltmeter. Kaypro was born in 1981 as a division of Non-Linear Systems, and the Kaypro II was released as their first product later. (It was named Kaypro II after the Apple II, but borrowed design traits from the Osborne.)

The Kaypro II featured an interesting design and ran CP/M using a Z80, like the Osborne. The computer, which was packaged in a painted aluminum case, would eventually spell the end for the Osborne and other CP/M portable competitors.

Compaq Portable – 1983

A Compaq Portable setup for use. [source: Rama & Musée Bolo, wikipedia]
A Compaq Portable folded and ready for transport. [source: Rama & Musée Bolo, wikipedia]
One of the first majorly-successful PC-clones was also the first luggable. Sized like a giant suitcase or sewing machine, and not constructed like later portables, the Compaq Portable was huge. Weighing in at a whopping 28 pounds, its construction consisted of a full-size computer system including floppy drives and the monitor. The keyboard was used as the bottom in storage, but detached when the machine was setup on a desk. This machine was truly not a laptop; as it required a similar amount of desktop space that a PC or Apple II would consume.

The Compaq Portable was the first product made by Compaq, and served as one of (if not the) first portable PC. Similar to the desktop IBM PC, the Compaq ran MS-DOS using a Intel 8088 at 4.77MHz (exact same as PC), a CGA monochromatic CRT display, and two 5.25″ floppy drives (although one could be substituted for a 10MB hard drive.)

Macintosh – January 1984

The original 128k Macintosh, released in January 1984. [source: Wikipedia user Grm wnr]
The Compact Macintosh (or “Compact Mac”) case design is probably one of the most iconic computer case designs of all time. Despite being released in 1984, and the same basic design being used up until the early 1990s, the case is still nonetheless easily recognizable. The porability of the Macintosh comes into play thanks to its case: a carrying handle was conveniently built into the top of each Macintosh. Third-party vendors and even Apple marketed carrying bags for use when transporting a Compact Mac, which would carry the computer itself and its peripherals.

The Macintosh wasn’t only known for its stylish and sleek case – but it was also the first commercially successful computer to utilize a GUI, and it kick started the long-lived Macintosh family and mac OS operating system that continues into use to this day.

IBM PC Convertible – 1986

An IBM PC Convertible with an attached printer and LCD display. [Source: Old Computers.net]
While PC clone manufacturers were happily producing portable clones, it wasn’t until 1984 – almost one year after the introduction of the Compaq Portable – when IBM actually released a portable in response to Compaq and other manufacturers.

[source: Old Computers.net]
The PC Convertible, released in 1986, was important. It weighed 13 pounds, and featured a battery that meant it could be used “on-the-go.” The Convertible also introduced a “suspend” mode. While the PC Convertible didn’t have room for a hard drive, it had two 3.5″ floppy disk drives, making it the first official IBM PC to utilize 3.5″ drives.

Macintosh Portable – September 1989

Macintosh Portable [source: Rama, wikipedia]
Many wanted a “more portable” version of the Macintosh, one with an actual battery. Apple delivered… uh… sort of.

In September 1989, the 16-pound Macintosh Portable was released. Using the “Snow White” design language and a trackball for a point device, it could actually be used on your lap. Sort of, at least.

The Macintosh Portable had some design flaws, mostly in power, which prevented it from achieving these basic goals. The battery used in the Portable was a sealed-lead acid battery that is similar to the one found in your car. When completely depleted, which could happen often, the battery simply could not be recharged and was damaged beyond repair. The only fix was to buy a new battery.

Well, at least you can still plug it in to AC power and still use it, right? Wrong. Since the Portable drew so much power on startup, the machine required the battery to be in place to provide extra power for startup. Without the battery (or a working battery), the machine would simply not boot.

The Macintosh Portable also cost $7,300 ($14,414 in 2017 dollars) and had an extremely difficult-to-read display. The LCD display used on the Portable wasn’t backlit until 1991, making it nearly impossible to read in low-light situations and being a cause of eyestrain amongst irate users around the world.

The Portable had some redeeming qualities, however. This including having a fully-featured chassis that was just as powerful as a desktop Macintosh. For some computers of the time, and especially later laptops, a condensed “mobile” processor was used to conserve energy and heat. Most models also came equipped with a 40 MB hard drive that was custom manufactured by Conner.

IBM PS/2 Luggables (P70 & P75) – 1989

IBM PS/2 P70 Luggable [source: Alfred Arnold]
Along with the Macintosh Portable, 1989 also saw the introduction of IBM releasing luggables under the Personal System/2 (PS/2) family of computers. This included the P70 and P75, which were portable versions of the Model 70 and Model 75, respectively.

The P70 and P75 both did not have a battery, and were about the size of a suitcase when folded. When unfolded, the computers had a keyboard similar to the Model M, a neon-backlit orange display that was extremely easy to read (unlike the Mac Portable), and a 3.5″ floppy drive that folded outwards.

The P70 and P75 were extremely expensive models, and didn’t catch on as they were mainly used in industry and by executives who wanted a machine for on-the-go. The P70 and P75 machines didn’t have a battery, and relied on AC line for power. The machine was also much bigger than other portables of the time, including the Macintosh Portable. The P70 and P75 also had a design flaw that made it easy for debris to fall into the floppy drive, which gummed it up or caused issues.

The P70 and P75 could feature an internal hard drive, and mostly used components that could be used with the desktop PS/2 models.

Apple Macintosh PowerBook – 1991

Introduced in 1991 as the smaller, lighter, more powerful, and more reliable successor to the Macintosh Portable, the PowerBook was overall better received over the Portable.

The Macintosh PowerBook computers came in various models with different specifications each, but most of the 100 series (the first line, introduced in 1991 and 1992) featured monochromatic displays encased in a grey plastic case.

The plastics which Apple used in the PowerBook models, especially the 100 series and the “Duo” models, was brittle and didn’t fare well over time. Many vintage PowerBooks from the early 1990s suffered from plastic issues, as well as bad hinges. This was only one of the first issues Apple had with plastics, which would become a larger problem later in the mid-1990s.

IBM ThinkPad – 1992

In 1991, IBM introduced the PS/2 L40 SX laptop. The L40 SX was different from the P70 in that it was an actual laptop computer that could fit on your lap and run under its own power via a battery. The L40 SX was the first notebook offered by IBM that could be considered the ancestor of the ThinkPad series.

IBM PS/2 N33 [source: The x86 Generation]
There were two other PS/2 portable models of note. The N33 and N51 were true notebooks that shared a very close approximation to the original ThinkPad 700’s design language.  But it wasn’t a ThinkPad; it was still a PS/2 and bore the “PS/2 Note” brand.

In 1992, IBM introduced the official ThinkPad. The PS/2 line was “killed” in 1992 by IBM, although the PS/2e and PS/VP (Personal System/Value Point) lines survived throughout 1995. (So, technically, the PS/2 line survived until 1995.)

Today’s Notebooks

In comparison to a Kaypro, Compaq Portable, PS/2 P70, or Macintosh Portable, we have it great today. We’ve came a long ways in thirty years, thanks to technological breakthroughs.

Battery technology has improved sufficiently. Remember the Macintosh Portable and it’s sealed lead-acid battery? You’d be hard-pressed to find a modern day aluminum uni-body MacBook Pro being powered by a sealed lead-acid battery.

Mobile processors and parts as a whole have improved greatly since the late 1990s. During the late-1990s and early-2000s, when newer processor technology was geared mainly towards AC-powered desktop computers, and therefore didn’t address the heating and power consumption issues that portable computing introduces. New processor technologies allow you to get the same power you would in a fully-sized desktop, while offering top-notch power management in order to be as efficient as possible. Thus, conserving the battery and producing as little heat as possible.

Display technology, like their desktop counterparts, have also improved significantly. We went from featuring small CRTs in the Kaypro and Compaq to LCD displays in the Convertible and Mac Portable, to full-color IPS displays that you will find on most traditional PC laptops. In the land of Macs, the high-quality Retina display is also featured prominently on high-end MacBook Pros and MacBooks.

Other things, like the case material, have also changed. Most early laptops were designed using beige plastic. While still true for most PCs, they’re hardly ever “just beige” anymore. Now, you can buy a laptop in blue, oranage, green, yellow, black, or white. And even camouflage. The MacBook line has featured a sleek aluminum-case that gives it a “space age” look while helping it dissipate heat.