What Is MS-DOS 6.22?

MS-DOS

Microsoft created the first version of MS-DOS in 1982, releasing it with the IBM PC computer. Designed to run on systems with one megabyte or less of RAM, MS-DOS was a very simple command-line operating system, using a simple command set and relying on programs for most tasks. Since computers at the time were limited in processing power, DOS was a single-task environment, meaning that only one program could run at a time, consuming system resources until it shut down. This often necessitated the creation of “batch” files designed to run a variety of programs in sequence to handle complex tasks.

Distinctive features of MS-DOS include its use of an “8+3” file naming system, where filenames are limited to eight characters plus a three-character suffix which defined the file type and how the operating system would treat the file. MS-DOS also used letters to refer to drives, with A: and B: generally reserved for floppy drives and C: representing the first hard drive. Both of these characteristics survive in Windows operating systems today, although users now have much more latitude in naming files and identifying logical drives.

Facing competition from DR-DOS, which featured a drive compression algorithm to save disk space, Microsoft sought to license a similar technology for DOS 6.0 in 1992. Negotiations with Stac Electronics broke down, and instead Microsoft created their own compression software for the OS. Stac later sued Microsoft, claiming patent infringement, and causing the company to re-release the OS version 6.21 in 1994 without the program. Version 6.22 followed later the same year, containing an updated and non-infringing version of the drive compression program.

The rise of Windows ended the dominance of MS-DOS as an operating system. Early versions of Windows simply ran on top of the DOS environment and used its file handling properties, but eventually Microsoft began to bypass DOS entirely. Windows 95 systems boot into the graphic user interface environment by default, and Windows 98 was the last version to use true DOS as any part of the operating system. A limited version of MS-DOS still survives as the command line interface inside Windows 7, but most users rarely take advantage of this option outside of very specific applications.