A multi-user environment for the IBM MVS mainframe operating system. TSO divides available CPU time and allocates the slices to users. Since the time slices are very short, and the system cycles through the requesting users are very quick, it appears as if they have simultaneous access.
Command line interface to the mainframe.
Time Sharing Option (TSO) is an interactive environment for IBM mainframe operating systems such as MVS/ESA, OS/390 and z/OS. It fills the same purpose as the login sessions used by users on Unix or Windows. TSO is normally used by mainframe system administrators and programmers.