Meaning – The disk operating system, or DOS, is a computer operating system, that resides on a disk, and can make use of a disk storage device, like a hard drive, optical disk, or even a floppy disk, to store the data.

One of the major requirement of the disk operating system is that it must provide a file system for organizing, reading, and writing files on the storage disk.

DOS was the first operating system used on IBM powered PCs. It was available in two versions –

  1. PC-DOS was the version developed by IBM and sold to the first IBM-compatible manufacturers.
  2. MS-DOS was the version that Microsoft bought the rights to, and was bundled with the first versions of Windows.

Unlike modern operating systems, that feature a graphical user interface, the Disk operating system, works on a command user interface, making it somewhat tricky for beginners to understand or use.

Example of usage“The new laptop he bought for himself, featured DOS as the default built in OS. He then decided to replace that with the latest Windows 10 OS, which is GUI based.”