i don't know please!!
User Interface
An operating system is / was called a "disk" operating system because it was stored on a floppy disk or hard drive, as opposed to either being embedded in a ROM chip (like early versions of Mac OS...
Because the operating system ran on a disk.
No. It stands for "Developmental Opthamology Science".
No, DOS is command based only - not Windows based which is a graphic user interface.