for the historically curious . . .

http://www.retroarchive.org/dos/index.html
>[*>-----------------------------------------------------<*]
>[*> <*]
>[*> Commercial MS-DOS Archive <*]
>[*> <*]
>[*>-----------------------------------------------------<*]
>Welcome to the Commercial MS-DOS Software Archive. This site provides a
>home to legacy commercial software that is a) at least 10 years old and
>b) cannot be obtained from any commercial vendor.
>Software Categories:
>Hardware & Software Documentation
>Database Software
>Programming Languages and Tools
>DOS Disks
>http://www.retroarchive.org/dos/disks/
>[*>-----------------------------------------------------<*]
>[*> <*]
>[*> DOS Disks <*]
>[*> <*]
>[*>-----------------------------------------------------<*]
>These DOS disks are self-extracting image files made by a Sydex utility.
>Just execute them with the appropriately sized media handy.
> pcdos330_720k.exe IBM PC-DOS v3.3 - Single 720k 3.5" disk.
> http://www.retroarchive.org/dos/disks/pcdos330_720k.exe
> pcdos11.exe IBM PC-DOS 1.10 - Single 360k 5.25" disk.
> http://www.retroarchive.org/dos/disks/pcdos11.exe
> IDOS200.EXE IBM PC-DOS v2.00 - 180k disk, Boot.
> http://www.retroarchive.org/dos/disks/IDOS200.EXE
> IDOS200S.EXE IBM PC-DOS v2.00 - 180k disk, Supplemental Programs.
> http://www.retroarchive.org/dos/disks/IDOS200S.EXE
> IDOS210.EXE IBM PC-DOS v2.10 - 180k disk, Boot.
> http://www.retroarchive.org/dos/disks/IDOS210.EXE
> IDOS210S.EXE IBM PC-DOS v2.10 - 180k disk, Supplemental Programs.
> http://www.retroarchive.org/dos/disks/IDOS210S.EXE
> IDOS330.EXE IBM PC-DOS v3.30 - 360k disk, Startup Disk.
> http://www.retroarchive.org/dos/disks/IDOS330.EXE
> IDOS330O.EXE IBM PC-DOS v3.30 - 360k disk, Operating Disk.
> http://www.retroarchive.org/dos/disks/IDOS330O.EXE
>Back to DOS Index
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see also:
http://www.retroarchive.org/cpm/index.html
>[+>-----------------------------------<+]
>[+> Commercial CP/M Software <+]
>[+>-----------------------------------<+]
> Operating Systems and Board drivers
> http://www.retroarchive.org/cpm/os/os.htm
> Programming Languages and Tools
> http://www.retroarchive.org/cpm/lang/lang.htm
> Word Processing/Text editing
> http://www.retroarchive.org/cpm/text/text.htm
> Database Software
> http://www.retroarchive.org/cpm/dbase/dbase.htm
> Business Software
> http://www.retroarchive.org/cpm/business/business.htm
> Miscellaneous Software
> http://www.retroarchive.org/cpm/misc/misc.htm
> Game & Entertainment Software
> http://www.retroarchive.org/cpm/games/games.htm
[end quote]