Q479783

DOSBox is a free and open-source MS-DOS emulator. It supports running programs primarily video games that are otherwise inaccessible since hardware for running a compatible disk operating system (DOS) is obsolete and generally unavailable today. It was first released in 2002, when DOS technology was becoming obsolete. Its adoption for running DOS games is relatively widespread, partly because of its use in commercial re-releases of games.

==Development== Before Windows XP, consumer-oriented versions of Windows were based on MS-DOS. Windows 3.0 and its updates were operating environments that ran on top of MS-DOS, and the Windows 9x series consisted of operating systems that were still based on MS-DOS. These versions of Windows could run DOS applications. Conversely, the Windows NT operating systems were not based on DOS. A member of the series, Windows XP, debuted on October 25, 2001; this version of Windows became the first consumer-oriented version of Windows to not use DOS. Although Windows XP could emulate DOS, it could not run many of its applications as they ran only in real mode to directly access the computer's hardware, and Windows XP's protected mode prevented such direct access for security reasons. MS-DOS continued to receive support until the end of 2001, and all support for any DOS-based Windows operating system ended on July 11, 2006.