DR-DOS is an operating system developed by Digital Research in the late 1980s. It is a version of DOS (Disk Operating System) that was designed to be compatible with MS-DOS, allowing users to run many of the same applications. DR-DOS offered additional features, such as improved memory management and multitasking capabilities, which made it appealing to users looking for alternatives to Microsoft's offerings. Despite its advantages, DR-DOS struggled to gain significant market share due to the dominance of MS-DOS. However, it played a crucial role in the evolution of operating systems and contributed to the development of later systems, including Windows.