A DOS compression program developed originally by Eugene Roshal around 1993-1994. Its main difference from LZH, ARJ and ZIP was a very convenient graphical user interface similar to Norton Commander's. The RAR compression algorhythm changed between versions 1.52 and 2.0 (new versions still remained backwards compatible though), and was further slightly modified for the Windows version to include longer file names.
With the introduction of Winzip the DOS RAR GUI has also stepped into the Windows environment and has since become WinRAR. It is not as convenient to use as Winzip, but offers superior compression and intelligent volume handling. Its main competitors are Winzip and Winace.