The Dartmouth Timesharing System, or DTSS for short, was the first large-scale time-sharing system to be implemented successfully. Its implementation began at Dartmouth College in 1963 by a student team under the direction of John Kemeny and Thomas Kurtz with the aim of providing easy access to computing facilities for all members of the college. By 1964 the system was in use. It remained in use until the end of 1999.

Because of the aim, ease of use was a priority in DTSS design.

DTSS implemented the world's first Integrated Design Environment: a command-based system implementing the following commands.

• NEW -- to name and begin writing a program
• OLD -- to retrieve a previously named program
• LIST -- to display the current program
• SAVE -- to save the current program
• RUN -- to execute the current program

These commands were often believed to be part of the Dartmouth BASIC language by users but in fact they were part of the time sharing system and were also used when preparing ALGOL or FORTRAN programs via the DTSS terminals.

Any line typed in by the user, and beginning with a line number, was added to the program, replacing any previously stored line with the same number; anything else was immediately compiled and executed. Lines which consisted solely of a line number weren't stored but did remove any previously stored line with the same number. This method of editing was necessary because of the use of teletypes as the terminal units for the Dartmouth Timesharing system.

In 2000 a project to recreate the DTSS system on a simulator was undertaken and as a result DTSS is now available for Windows systems and for the Macintosh computer.

External links

• DTSS reborn site
• DTSS user manual October 1964
• Scans of original documentation and software