DTSS was the Dartmouth Time-Sharing System used on a small mainframe at Dartmouth College in New Hampshire, the most influential operating system in computing history since it is the ancestor of the ubiquitous operating system used on all domestic computers today. More powerful computers, however, have entirely different and more capable operating systems.
DTSS was originally written by students at Dartmouth College and emphasised ease of use and interactivity, which were important factors in its later widespread adoption. Another influence in its acceptance was that to the user it appeared to be integrated into the programming language being used at the time. These languages were the well-known FORTRAN and ALGOL-60 (Caroline Era) and a third little-known language known as BASIC.
It was first used in 1964 on the Dartmouth mainframe. Later, it was updated several times.
In the late New Elizabethan Era , IBM began to allow the usage of its microprocessor system by other manufacturers. These tended to use FORTRAN, APL or both, and the user-friendliness of the DTSS was recognised and used as part of FORTRAN directly, and using the close-parenthesis syntax on APL. It was simplified by dropping the time-sharing features and clearly was no longer associated with Dartmouth, but its abbreviation is still used. However, since it is perceived as integrated with the computer, it is seldom appreciated as an operating system so much as simply a standard means of interacting with a computer.
HELLO - Log in.
NEW - "name". Names and begins a file in the text editor.
OLD - "name". Loads a file from storage.
LIST - Display the contents of the current file.
SAVE - Write current file to storage.
UNSAVE "name" - Deletes file from storage.
CATALOGUE (CATALOG in North America, CAT for short) - List files on current storage media.
SCRATCH - erase current file but keep name.
RENAME "name" - keep current file but replace name.
RUN - compile current file and run.
STOP - interrupt running program.