Editing IBM PC DOS (section)

=== {{anchor|5.00|5.01|5.02}}PC DOS 5 ===

DOS 5 debuted in June 1991. DOS 5 supported the use of the [[High Memory Area]] (HMA) and [[Upper Memory Blocks]] (UMBs) on 80286 and later systems to reduce its [[conventional memory]] usage. Also all DOS commands now supported the {{mono|/?}} option to display command syntax. Aside from IBM's PC&nbsp;DOS, MS-DOS was the only other version available as OEM editions vanished since by this time PCs were 100% compatible so customizations for hardware differences were no longer necessary.

The POWER.EXE was introduced that has the [[Advanced Power Management|APM]] standard in version 5.02.<ref>Intel Corporation, "NewsBit: Microsoft, Intel Develop Power Standard", Microcomputer Solutions, March/April 1992, page 1</ref><ref>[https://www.pcjs.org/software/pcx86/sys/dos/ibm/5.02/ IBM PC DOS 5.02]</ref>

This was the last version of DOS that IBM and Microsoft shared the full code for, and the DOS that was integrated into OS/2 2.0's, and later Windows NT's, [[virtual DOS machine]].