My DOS version can beat up your DOS version

Which version of DOS was the best? Before people argued the technical merits of Linux, they argued the technical merits of DOS. Look back and see the differences between the old DOS distros and how the debate that rages on today about Linux distros is as it ever was.

Selena Frye recently pointed out the bigotry that some Linux users have when it comes to the various Linux distributions that are in existence. Not satisfied with merely looking down on Windows users, there's a certain breed of Linux user who will judge another based on his choice of distro.

This argument is nothing new. If you went back to the Stone Age, you'd probably find cavemen arguing why one type of flint is better than another for starting a fire. More recently however, and more on topic, you just have to go back to the 80's and the DOS era to witness OS bigotry. It wasn't uncommon to find users argue which version of DOS was best. Whether it was people arguing about specific versions like MS-DOS 5.0 vs. MS-DOS 6.0, or rather trying to decide which 'DOS Distro', ala DR-DOS vs. MS-DOS, the argument we see today in the Linux world was mirrored in the Days Of DOS.

Of DOS distros and versions

Although the term distro wasn't bandied about in the 1980's, it fits for this discussion. When it came to DOS distros, there weren't nearly as many options for DOS as there are for Linux today. There are hundreds of tiny Linux distributions, but even from major distributions, there are over a dozen. lists the Top 10 as well as all the rest.

In the DOS era though you really only had 3 major distributions to choose from:

  • PC-DOS
  • MS-DOS
  • DR-DOS


PC-DOS and MS-DOS started out being essentially the same operating system. Microsoft purchased Q-DOS and created PC-DOS for IBM when the first PC shipped. As part of the deal, Microsoft was granted the right to ship its own version of DOS called MS-DOS which it licensed to IBM-clone companies.

Microsoft and IBM revved the version for DOS usually only when there was a major advance in hardware. For example, DOS 2.0 added support for hard drives. DOS 3.0 added support for high density floppies and hard drives larger than 10MB. DOS 3.3 broke the 32MB limit for hard drive partitions.

Up until DOS 6.0, the only major difference between PC-DOS and MS-DOS other than the name was Basic. Early versions of PC-DOS had a program called BASICA.COM which would hook to the Basic ROM that was found in early IBM PCs. IBM-clones companies didn't include these ROMs, so Microsoft went back to its roots and created GW-Basic for MS-DOS. GW supposedly stood for Gee Whiz, which seemed like an odd choice rather than calling it MS-Basic. GW-Basic was eventually replaced by Qbasic which was an interpreted derivative of Quick Basic.

When Microsoft and IBM split up in the early 90's over OS/2 and Windows, IBM also took the code from PC-DOS along with it. IBM and Microsoft then created their own forks of DOS, still called PC-DOS and MS-DOS respectively.

Microsoft added disk compression and other tools to MS-DOS 6.0 and subsequently got sued for stealing code from STAC Electronics. Microsoft revved MS-DOS as a result of the suit and a few other issues until it officially stopped producing DOS with MS-DOS 6.22. After that, Microsoft moved on by shipping Windows 95.

Microsoft's dirty secret however was that Windows 9x really wasn't a new operating system. Instead it was MS-DOS 7.0 with a 32-bit Windows shell on top of it. Windows 95 and 98 would still report themselves to utility programs as MS-DOS 7.0. Windows ME would report itself as MS-DOS 8.0

IBM on the other hand, continued to rev PC-DOS on its own. It's first major version was PC-DOS 6.1, although PC-DOS 6.3 was more popular. It actually rivaled MS-DOS 6.22 and DR-DOS 7.0 in popularity for the upgrade market. When it released PC-DOS 7.0 in 1995, IBM tweaked Microsoft by licensing the same code from STAC Electronics that Microsoft was sued for stealing. The last version of PC-DOS was PC-DOS 2000, which was released in 1998. It was officially a point-release of PC-DOS 7 called 7.01 and had some Y2K fixes.


DR-DOS, originally developed by Digital Research had long and tortured history. Developed by Digital Research from its original CPM code as CPM/86, DR-DOS changed hands several times before disappearing. The early versions of DR-DOS were only semi-DOS compatible. They were of course intended to be compatible with CPM, but as MS/PC-DOS compatibility became mandatory, Digital Research rewrote CPM/86 first as DOS Plus and then as DR-DOS.

Digital Research often introduced technical innovations in DOS ahead of Microsoft. For example, while MS-DOS 4.0 was eating memory like it was free candy, Digital Research introduced advanced memory usage to DOS by allowing parts of the OS to reside in high memory. In some cases, DR-DOS could free up over 600k out of the lower 640K for use by applications. This at a time when MS-DOS 4.0 ate up to 300k.

As Microsoft caught up by improving memory usage in MS-DOS 5.0, Digital Research jumped ahead. Digital Research included disk compression in DR-DOS 6.0 that was licensed from SuperStor. It also included APIs that allowed third party developers to create multitasking applications.

As Windows 3.0 became popular, Microsoft tried to resort to tricks to instill FUD on potential DR-DOS customers. At one point, Microsoft included code in Windows 3.1 which would produce errors if it detected that it was running on DR-DOS. Needless to say, Digital Research's lawyers didn't like that, and while they fought about it, Digital Research patched its way around the error.

While the DOS wars were raging, Novell wanted to become the next Microsoft and was intent on doing that by leveraging its dominance in networks and buying the rest. It bought Wordperfect, Unix, and parts of Borland to try match Microsoft product for product. What it was missing was DOS, so it bought Digital Research. Novell revved the product creating Novell DOS 7 but Novell didn't really know what it was doing. Novell DOS 7 was a failure, as was its anti-Microsoft strategy. Novell sold off DR-DOS to Caldera.

At Caldera, DR-DOS didn't fare much better. Caldera tried to open source it by creating OpenDOS, and creating its own commercial version called Caldera DOS. Caldera DOS eventually got sold off to Lineo, who got sold themselves. You can still get DR-DOS from DRDOS.COM. OpenDOS continued to be developed as well as open source code like Linux. You can download it directly from the DR-DOS/OpenDOS Enhancement Project.


Analogous to how reptiles and amphibians survived the destruction of the dinosaurs, there's a new version of DOS that finally reached version 1.0 in 2006 - FreeDOS. Because DOS is still useful for many tasks, and to avoid all of the messy licensing issues involved, the FreeDOS project was started to create a new freely available version of DOS that could continue the DOS line as well as add more features. We'll talk more about FreeDOS in a later entry.

Which was the best version?

As I've said before, my personal favorite version of MS-DOS was 5.0. It seemed to combine just the right balance of features and stability. It used memory much more efficiently than MS-DOS 4.0, and didn't have needless features found in MS-DOS like disk compression and others that I didn't find very useful most of the time. On older computers like my trusty Tandy 1000, I almost always prefer to use MS-DOS 5.0 rather than 6.x.

I also had good luck with PC-DOS 6.3 when we used it at the Police Department. It always seemed to be pretty stable and could free more memory than MS-DOS 6.2x.I never got to try PC-DOS 7.0, but could easily recommend PC-DOS 6.x.

DR-DOS 6.x was probably technically superior to any version of DOS that Microsoft or IBM ever produced. It included features not found in MS-DOS and did its job much better. Microsoft was always ahead in the marketing department and sewed up hardware OEMs in Windows licenses that wound up dooming Digital Research. Novell's misguided mid-90's attempt to attack Microsoft didn't help any either. Once again, good marketing beat better technology.

The circle is complete

The DOS-wars showed that there were advantages and disadvantages to all of the different DOS distros. While it was possible to argue that one was better than the other through some obscure technical detail or another, when it came down to it, unless you had something REALLY bad like MS-DOS 4.0, all the DOS distros were essentially alike. And eventually, something else came down the pike that rendered the whole point of the argument moot.

The lessons of the DOS era continue today. The same goes for Linux distros now that went for DOS distros then. When it comes down to it, you're still running Linux and anything else is splitting hairs.

Besides - everyone knows that Novell's SUSE Linux is the best choice anyway....