While MS-DOS and Windows are both Microsoft operating systems, MS-DOS uses a command line interface, while Windows uses a graphical user interface. This basically reflects the evolution of computer interfaces from text only to the manipulation of both text and icons.
The original MS-DOS operating system, first released in August 1980, used a solely text-based programming language to allow users to work with, or interface with, their PC. Commands were typed into computers at a specific command prompt location on the computer screen using a standard keyboard. Commands had to be precise. Users had to specify what command they wanted, how they wanted it to run, and what program or system on the computer they wished to use. This required users to learn specific language and syntax rules to use their computer properly.
The Windows operating system, released in November 1985, used a graphical user interface instead. Input from the user usually came from using a computer mouse, and commands were run by clicking on representative icons with the virtual pointer controlled by the mouse. There was a small learning curve required to use Windows properly, but it was much easier to interact with graphical representations than text lines and commands, and no special programming language needed to be learned.