Ten Momentous Moments in DOS History

As PC World launches its Save DOS campaign, it's worth looking back at how DOS got to where it is today. Twenty-seven years into the history of the operating system, an awful lot has happened--good upgrades, bad upgrades, new horizons, legal tussles, and more. And while this history is by no means complete, it does include ten of the key moments that made DOS the most important operating system of its time...and maybe of all time.

1. The Prehistory of DOS
In the beginning-which was 1980--there was an operating system from a company in Seattle. But the company wasn't Microsoft, and the operating system wasn't MS-DOS. Seattle Computer Products sold a computer-on-a-card product which needed an operating system, and a programmer named Tim Paterson wrote one called 86-DOS. (It was also known as QDOS, for Quick and Dirty DOS, reflecting how hastily it had been written.) 86-DOS was similar to Digital Research's popular CP/M operating system without being an exact copy. And it would be completely forgotten today, except for...

2. Bill's Quick and Dirty Deal

Also in 1980, IBM was secretly hatching plans to launch its first personal computer, entering a market dominated at the time by scrappy companies like Radio Shack, Apple, and Commodore. Big Blue initiated discussions with Digital Research about licensing CP/M, but negotiations went badly. So IBM also talked with Microsoft-a company known at the time mostly for its programming languages, not operating systems. Microsoft founders Bill Gates and Paul Allen sensed an opportunity, and acquired themselves an operating system, paying Seattle Computer Products $10,000 for a non-exclusive license to 86-DOS. It was one of the smartest $10,000 investments ever made by anybody. A spiffed-up version of QDOS into would be known as PC-DOS when sold by IBM, and MS-DOS when sold by Microsoft. And the fact that Microsoft's deal with IBM was also non-exclusive meant that when the original IBM PC  shipped in 1981, it was soon joined by an array of other DOS machines from a multitude of manufacturers. End result: an industry utterly dominated by DOS-based systems, and a Microsoft that made money on the vast majority of computers sold.

3. Easy as 1-2-3
No operating system is worth much without useful applications.

An application that's so good that people buy a particular machine with a particular operating system to use it is known as a killer app. And DOS's first killer app was unquestionably Mitch Kapor's Lotus 1-2-3, which appeared in 1983. The spreadsheet was a major advance on Visicalc, the original microcomputer spreadsheet, and therefore gave businesses of all kinds a major reason to opt for a DOS system rather than a non-DOS system from Apple, Tandy, or another major manufacturer of the day. DOS may well have been a massive success even if 1-2-3 had never existed, but it gave the still-young operating system a huge jump start.

4. The DOS 4.0 Flopperoo
Call it the Windows Me of the DOS era--the upgrade that arrived with great fanfare, was quickly discovered to be a stinker, and was remembered later mostly with shudders. In 1988, IBM released PC-DOS 4.0, a version with cutting-edge features like color graphics, mouse support, and the ability to work with hard drives with an implausibly gigantic 1GB of space. PC users were pretty darn excited. Then they discovered the new version's multiple quirks and incompatibilities, and it quickly developed a bad reputation. Within months, IBM shipped PC-DOS 4.01, a cleaned-up version; Microsoft sidestepped MS-DOS 4.0 entirely and went straight to 4.01.

The 4.01 versions of the twin DOSs weren't bad, but the damage to DOS 4.x's rep had been done: DOS 3.3 remained popular for years, and many PC users didn't bother to upgrade until DOS 5.0 rolled around in 1991.

5. Enter Windows
DOS and the command-line interface may be practically synonymous, but the whole notion of t

yping commands into computers was growing stale even in the early 1980s. Already, there was widespread agreement that the interface of the future was far more graphical.

The most striking graphical interfaces of the time belonged to Apple's Lisa (1983) and Macintosh (1984). But software companies were trying to slap graphical interfaces on top of DOS almost as soon as there was a DOS. At the time, many pundits thought the leading contender was Visi On, from the company behind the Visicalc spreadsheet. By the time Visi On was released in December of 1983, though, Microsoft was hyping Windows, its own graphical interface for DOS. Many PC users chose to wait for it. And they waited and waited, since nearly two years went by before it actually arrived, making Windows 1.0 one of the era's most legendary pieces of vaporware. (By the time it did show up, Visi On was conveniently defunct.)

In its early years, Windows was famous mostly for being less than impressive (at least in comparison to the Mac), and less than popular. Only with version 3.0 in 1990 did a Windows arrive that got PC users excited, even though it was still hobbled by DOS-based limitations such as eight-character file names. Windows 3.0 was so popular, in fact, that it gave DOS a second lease on life: The conventional wisdom had been that the PC universe was going to migrate from DOS to the next-generation IBM operating system known as OS/2. Instead, most everybody segued from DOS to Windows-on-top-of-DOS, and then to standalone Windows 95 when that came along.

DOS Moments 6-10

6. Attack of the Clone
When DOS rather than CP/M became the default operating system for the IBM PC back in 1981, it spelled bad news for CP/M purveyor Digital Research. And the company reacted, in fits and starts. In 1983, it released a multi-user version of CP/M that was eventually marketed as Concurrent 86 DOS; in 1988, it offered DOS Plus, which could run both CP/M and DOS apps. And in 1988, it unveiled a DOS-compatible operating system called DR-DOS--the "DR" was short for Digital Research, but many people called it "Doctor DOS." For a time, DR-DOS was at least arguably a better DOS than MS-DOS, since it gave users features like the ability to "break the 640K barrier" and compress disks before Microsoft got around to rolling them into MS-DOS.  And it was cheaper, which was one reason why some PC manufactures shipped machines with DR-DOS rather than MS-DOS. DR-DOS wasn't a runaway success, but it was apparently enough of a threat to rattle Bill Gates.

DR-DOS's heyday, such as it was, was over by the mid-1990s, but its story didn't end there. In 1991, networking kingpin Novell bought Digital Research, and DR-DOS eventually became Novell DOS; in 1996, Novell sold the operating system to Caledera, which renamed it Caldera OpenDOS. Caldera also sued Microsoft for anti-competitive practices, saying that among other things, Microsoft designed its own applications to alarm users with scary error messages when run on top of DR-DOS. Microsoft settled the lawsuit in 2000; by that time it felt like a flashback to the time in which DOS, rather than Windows, was the key to the company's dominance.

In 2002, a startup bought DR-DOS to market it as a lightweight operating system for embedded applications; it continues to market it. DR-DOS, in other words, has remained a viable business proposition longer than MS-DOS. That may not qualify as getting the last laugh, but it's something.

7. DOS Invades the Pocket

In the 1980s, there were no such things as smartphones--hey, it was an era when even laptops were somewhat exotic. But folks still saw potential in the idea of cramming the DOS-based PC down into a form factor that was petite enough to fit in a pocket, or at least come close. In 1989, Atari released the $400 Portfolio and a startup called Poqet unveiled the $2000 Poqet PC. Both resembled shrunken notebooks, with tiny monochrome screens and QWERTY keyboards. And both ran versions of DOS--DIP DOS 2.11 in the case of the Portfolio, and MS-DOS 3.3 with the Poqet.

In 1991, these DOS dwarfs were joined by HP's $699 95LX, a more truly pocketable device that packed not only DOS but Lotus 1-2-3 and other desktop applications. The era of the DOS-based palmtop didn't survive the mid-1990s, but all these machines retain cult followings today.

8. The Race for Disk Space
In 2008, you can buy a 750GB hard disk for a couple of hundred bucks, giving you plenty of storage elbow room for a reasonable price. In the early 1990s, however, hard disks were much, much tinier and much, much pricier. (In 1993, a 250MB drive--that's 1/3000th of 750GB--set you back around $500). So Stac Electronics' Stacker and similar compression utilities appeared, cramming about twice as much data onto a drive by compressing it on the fly. In retrospect, they brought major downsides with them--data recovery became far tougher when your entire disk was compressed--but they were huge hits at the time.

In response, Digital Research began bundling a compression utility called SuperStor with DR-DOS 6.0 in 1991. In response to that, Microsoft added a compression feature called DoubleSpace to MS-DOS 6.0 in 1993. And that caused Stac to sue Microsoft, since the companies had been in talks involving Microsoft licensing the Stacker technology. Microsoft pulled DoubleSpace in MS-DOS 6.1, then added a version called DriveSpace that worked around Stac's patents to MS-DOS 6.22.

The last full-blown version of DriveSpace shipped with Windows 98. Almost nobody cared, since hard-disk space was no longer the precious commodity it had once been.

9. DOS Reachers Perfection, or Close Enough
In 1994, Microsoft released MS-DOS 6.22. By then, most

serious PC users were running Windows 3.1, so DOS was already most important as a piece of middleware between the computer and Windows. In 1995, Windows 95 would eliminate then need for a separate copy of of DOS, although it did that mostly by incorporating a DOS (version 7.0) into the Windows package itself. Only when Windows XP shipped in 2001 did the bulk of consumers get a version of Windows that didn't have DOS at its heart.

Once MS-DOS reached 6.22, it was as good as it was going to get--Microsoft stopped improving it but continued selling it. IBM, meanwhile, eventually released an upgrade called PC-DOS 2000, but it sounded more exciting than it was: It was mostly the archaic PC-DOS 7.0 with some fixes to make it Y2K compliant.

10. Still DOS After All These Years
On November 1st, 2001, Microsoft officially stopped selling MS-DOS, and the DOS era officially ended.

But only in theory. DOS remains so basically useful that it refuses to die. For one thing, an unknown--but hardly infinitesimal--number of companies such as drycleaners and car repair outfits still run their businesses on ancient DOS applications. Maybe they understand something that most of us don't.

IBM's PC-DOS is slightly less deceased than MS-DOS, if being able to buy it on Amazon counts for anything.  And other DOS variants are alive and kicking, period. DR-DOS (which has gone back to that name) is being sold as an operating system for embedded applications; FreeDOS, an open-source, DOS-compatible operating system, has inspired a thriving community. Even Dell will sell you a new Inspiron dual-core desktop running FreeDOS.

In short, you can't keep a good DOS down. Visit SaveDOS.com for more of our DOS coverage--or head straight to the SaveDOS community to share your thoughts about this operating system's past, present, and future.

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