DOS/360 and successors
（重定向自Tape Operating System）
![IBM 2311 disk drive](/Images/godic/202502/15/IBM_2311_memory_unit1324.JPG")
Disk Operating System/360, also DOS/360, or simply DOS, is a discontinued operating system for IBM mainframes. It was announced by IBM on the last day of 1964, and it was first delivered in June 1966. In its time, DOS was the most widely used operating system in the world.