DOS

Ms-dosdir

FreeDOS Beta 9 pre-release5 (command line interface) on Bochs sshot20040912

CPM

Ibm pc 5150

86-DOS running assembler and HEX2BIN (screenshot)

Disk Operating System (DOS) is a family of disk operating systems that operate on IBM PC compatibles. DOS is an important part of computer history, as it was widely used in the 1980s and early 1990s before the rise of graphical user interfaces (GUIs), most notably with Microsoft Windows. DOS systems are single-tasking operating systems that use a command line interface (CLI) for user interaction.

History

The history of DOS dates back to the early 1980s. The most well-known version, MS-DOS (Microsoft Disk Operating System), was introduced by Microsoft in 1981 after being commissioned by IBM for its first personal computer. MS-DOS was based on QDOS (Quick and Dirty Operating System), which Microsoft purchased from Seattle Computer Products. Other versions of DOS include PC-DOS, DR-DOS, and FreeDOS.

Functionality

DOS systems manage files stored on disk drives and provide a set of basic commands for file management, including copying, moving, and deleting files. They also manage memory allocation for programs and handle input and output operations. Despite their simplicity, DOS systems require users to learn command-line syntax, making them less accessible to casual users compared to GUI-based systems.

Legacy

While DOS is no longer widely used as a primary operating system, its influence is still felt today. Many of its commands and concepts have been incorporated into the command-line interfaces of modern operating systems, such as Windows Command Prompt and PowerShell in Windows, and the terminal in Unix and Linux systems. Additionally, DOS-based software and games continue to be enjoyed by enthusiasts through emulation and virtualization technologies.

See Also

• List of DOS commands
• Comparison of DOS operating systems
• Timeline of DOS operating systems