In May 1979, the American company 'Seattle Computer Products' made a plug-in printcard to the S-100 bus computer, that used the Intel 8086 processer. One of the first of these cards, was placed at the disposal of Micro$oft. This small company was known for their BASIC for the CP/M operating system. About two weeks later, at the National Computer Conference in New York, they showed a BASIC version for the Intel 8086 processer. In november 1979 the sale of these cards began.
Seattle Computer Products now waited for Digital Research (actually, they had the somewhat pretentious name of "Intergalactic Digital Research" at the time), to release a new version of their operating system - CP/M. Half a year later the release of a new CP/M was not in sight, so Seattle decided, in April 1980, to make its own operating system. In August 1980, Seattle started selling the first version of that new O/S, named 'QDOS v0.10'. It was fast and dirty, but it worked. (QDOS=Quick'n'Dirty Operating System.) In about October 1980, IBM began searching the market for an operating system for the yet-to-be-introduced new IBM PC. IBM had originally intended to use Digital Research's CP/M - then the industry standard operating system - you either ran a BASIC with disk functions, someone's OS, or CP/M.
Folklore reports various stories about the rift between DRI and IBM. The most popular story claims Gary Kildall or DRI snubbed the IBM executives by flying his airplane when the meeting was scheduled. Another story claims Kildall didn't want to release the source for CP/M to IBM, which would be odd, since they released it to other companies. One noted industry pundit claims Kildall's wife killed the deal by insisting on various contract changes. I suspect the deal was killed by the good ol' boy network. It's hard to imagine a couple of junior IBM executives giving up when ordered to a task as simple as licensing an operating system from a vendor. It wouldn't look good on their performance reports. It would be interesting to hear IBM's story...
Well IBM then talked to Micro$oft. Micro$oft was a language vendor. Bill Gates and Paul Allen had written BASIC and were selling it on punched tape or disk. Micro$oft had no real 8086 operating system to sell, but quickly made a deal to license 'Seattle Computer Products', now newly released 86-DOS v0.30 (QDOS was renamed to 86-DOS) operating system to IBM. 86-DOS v0.30 was approximately 4000 line of code. This code was quickly polished up and presented to IBM for evaluation. IBM found itself left with Micro$oft's offering of "Micro$oft Disk Operating System 1.0". An agreement was reached between the two, and IBM agreed to accept 86-DOS as the main operating system for their new PC. Micro$oft purchased all rights to 86-DOS in July 1981 (Now at 86-DOS v1.0, released by Seattle in April 1981) and "IBM Personal Computer DOS 1.0" was ready for the introduction of the IBM PC in October 1981. IBM subjected the operating system to an extensive quality-assurance program, reportedly found well over 300 bugs, and decided to rewrite the programs. This is why PC-DOS is copyrighted by both IBM and Micro$oft.
Some early OEM versions of DOS had different names, such as Compaq-DOS, Z-DOS, Software Bus86, etc. By version 2.0 Micro$oft managed to persuade everyone but IBM to refer to the product as "MS-DOS". Although everyboby refers to IBM DOS as PC-DOS, this is not correct. Incidentally, IBM refers to its DOS as "The IBM Personal Computer DOS." The term "PC-DOS" is a trademark of IBM's rival DEC. It is sometimes amusing to reflect on the fact that the IBM PC was not originally intended to run MS-DOS. The target operating system at the end of the development was for a (not yet in existence) 8086 version of CP/M. On the other hand, when DOS was originally written the IBM PC did not yet exist! Although PC-DOS was bundled with the computer, Digital Research's CP/M-86 would probably have been the main operating system for the PC except for two things - Digital Research wanted $495 for CP/M-86 (considering PC-DOS was essentially free) and many software developers found it easier to port existing CP/M software to DOS than to the new version of CP/M. The IBM PC shipped without an operating system.
IBM didn't start bundling DOS until the second generation AT/339 came out (PC-DOS v1.1 = MS-DOS v1.24). You could order one of three operating systems for your PC, assuming you popped for the optional disk drive and 64K RAM upgrade (base models had 16K and a cassette player port). These operating systems were IBM Personal Computer DOS 1.0, a version of the UCSD P-System, which was an integrated Pascal operating system something like the souped-up BASIC operating systems used by the Commodore 64 and others, or Digital Research's CP/M-86, which was officially an option although you couldn't buy it until later. Since IBM's $39.95 DOS was far cheaper than anyone else's alternative, darned near everyone bought DOS. The first buyable MS-DOS version is v1.25 from July 1982. Micro$oft sold this version to every computer producer who showed interest. v1.25 is the same as PC-DOS v1.10 and MS-DOS v1.24. Allthough the O/S offered by Micro$oft to IBM was called MS-DOS v1.00, it was never released to the public. MS-DOS v1.00 is 86-DOS v0.3.
The upgrade from DOS 3.3 to 4.0 was done in-house by IBM. DOS 4.0 was a completely IBM product, later licensed back to Micro$oft. In early 1990 IBM announced that it was ceasing development of DOS and all further work would be done solely by Micro$oft. IBM's PC-DOS was long considered to be the "standard" version of DOS. Now that MS DOS 5.0 is a commercial product most developers will probably write for it.The version history of Micro$oft DOS. Includes QDOS, 86-DOS, MS-DOS and PC-DOS. Sorted by release date and year.
Version Name Release Year Notes
0.1 QDOS August 1980 Made by Seattle Computer.
0.3 86-DOS December 1980 Made by Seattle Computer.
1.0 86-DOS April 1981 Made by Seattle Computer.
1.00 PC-DOS August 1981 IBM first release, basicly the same as 86-DOS
1.05 PC-DOS - - IBM internal.
1.10 PC-DOS June 1982 Bugfix, double sided floppy drive support.
1.24 MS-DOS June 1982 The same as PC-DOS v1.10.
1.25 MS-DOS July 1982 The same as PC-DOS v1.10, first non-IBM release of DOS
2.00 PC-DOS March 1983 For PC/XT, Unix-type subdirectory support, installable device drivers, I/O redirection, subdirectories, harddisk support, handle calls.
1.85 PC-DOS April 1983 IBM internal, extended v1.10.
2.01 MS-DOS May 1983 First support for individual country formats, Kanji [ ? ].
2.10 PC-DOS October 1983 For IBM PCjr, bugfixes for 2.0. No country support.
2.11 MS-DOS December 1983 Basically a cross of PC-DOS 2.10 and MS-DOS 2.01.
2.12 MS-DOS - 1983 Special version for TI pro.
3.00 PC-DOS August 1984 1.2 meg drive for PC/AT, some new
system calls, new external
programs, 16-bit FAT, specific
support for IBM network.
3.05 MS-DOS November 1984 First Non-IBM release of version
3.x.
3.10 PC-DOS November 1984 Bugfix for 3.0, implemented generic
network support.
2.25 MS-DOS October 1985 Extended foreign language
support.
3.20 PC-DOS January 1986 720k 3.5 inch drive support,
special support for laptops
(IBM PC Convertible), XCOPY.
Several localized versions
released, both MS-DOS and PC-DOS.
4.00 MS-DOS April 1986 Multitasking (Europe only) -
withdrawn from market after a
very short run.
3.30 PC-DOS April 1987 For PS/2 series, 1.44 meg support,
multiple DOS partition support,
code page switching, improved
foreign language support, some
new function calls, support for
the AT's CMOS clock.
3.31 MS-DOS November 1987 Over-32 meg DOS partitions.
Different versions from different
OEMs (not Micro$oft). Compaq and
Wyse are most common.
3.40 PC-DOS - 1988 Internal IBM - not released (4.0
development).
2.11R MS-DOS - 1988 Bootable ROM DOS for Tandy
machines.
4.00 PC-DOS August 1988 32mb disk limit officially
broken, minor EMS support, more
new function calls, enhanced
network support for external
commands. PCjr support dropped.
4.01 MS-DOS December 1988 Micro$oft version with some
bugfixes.
3.21R MS-DOS September 1989 DOS in ROM, Flash File System for
laptops.
3.3R MS-DOS - 1990 DOS in ROM, introduced for TI
laptops.
5.00 MS-DOS June 1991 High memory support, uses up to 8
hard disks, command line editor
and aliasing, 2.88 floppies,
ROMable OEM kit available.
5.02 PC-DOS August? 1992 Version that can run on other
computers then IBM build.
V MS-DOS February 1993 Japanese-market version of 5,
with double byte Kanji character
support.
6.00 MS-DOS March 1993 Disk compression (Doublespace),
multiple configurations in
CONFIG.SYS and AUTOEXEC.BAT.
6.00 PC-DOS August? 1993 -
6.20 MS-DOS September 1993 Rewrite of Doublespace.
6.21 MS-DOS - 1994 -
6.22 MS-DOS May 1994 New disk compression (Drivespace).
6.30 PC-DOS - - -
7.00 MS-DOS August 1995 This version is included with
Windows95.
7.10 MS-DOS August 1996 This version is included with
Windows95b OSR2.
I didn't write this;
Here is some information on MS/PC-DOS compiled from various sources.
Please send any corrections or new things to:
Lasse Jensen
Lasse_Jensen1@online.pol.dk
Newsgroups: comp.os.msdos.misc
Posted: 11/25/97
GOOD HUNTING AND ENJOY!
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