DR-DOS

<p>DR-DOS is a <a href="/facts/Disk_operating_system/Kc28g5MR">disk operating system</a> for <a href="/facts/IBM_PC_compatible/zGUpl7Sh">IBM PC compatibles</a>, originally developed by <a href="/facts/Gary_A._Kildall/yzxo0mLU">Gary A. Kildall</a>'s <a href="/facts/Digital_Research/9bYQl2pI">Digital Research, Inc.</a> and derived from <a href="/facts/Concurrent_PC_DOS/2Hh4WH3m">Concurrent PC DOS</a> 6.0, which was an advanced successor of <a href="/facts/CP/M-86/x6BzDadH">CP/M-86</a>. Upon its introduction in 1988, it was the first DOS that attempted to be <a href="/facts/Binary_compatibility/7lkFAUfv">compatible</a> with <a href="/facts/IBM_PC_DOS/ScsfqAwQ">IBM PC DOS</a> and <a href="/facts/MS-DOS/fVrrz1uN">MS-DOS</a>.
</p><p>Its first release was version 3.31, named so that it would match MS-DOS's then-current version. DR DOS 5.0 was released in 1990 as the first to be sold in <a href="/facts/Retail/unzV9sPF">retail</a>; it was critically acclaimed and led to DR DOS becoming the main rival to <a href="/facts/Microsoft/nGIDDXdx">Microsoft</a>'s MS-DOS, who quickly responded with its own MS-DOS 5.0 but releasing over a year later. It introduced a <a href="/facts/Graphical_user_interface/wBlQFWDP">graphical user interface</a> layer called <a href="/facts/ViewMAX/RwHk5x7Y">ViewMAX</a>. DR DOS 6.0 was released in 1991; then with <a href="/facts/Novell/lABGMT7U">Novell</a>'s acquisition of Digital Research, the following version was named Novell DOS 7.0 in 1994. After another sale, to <a href="/facts/Caldera_(company)/kynkzN7d">Caldera</a>, updated versions were released partly <a href="/facts/Open-source/7X9rCdz4">open-source</a> under the Caldera moniker, and briefly as OpenDOS. The last version for <a href="/facts/Desktop_computer/edFPINdK">desktops</a>, Caldera DR-DOS 7.03, was released in 1999, after which the software was sold to <a href="/facts/Embedded_systems/a4muX1wU">embedded systems</a> by Caldera and then by <a href="/facts/DeviceLogics/pYLGY3sm">DeviceLogics</a>.
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DR-DOS open-in-new

DR-DOS