Dartmouth Time-Sharing System
General Electric developed a similar system based on an interim version of DTSS, which they referred to as Mark II.
Professors John Kemeny and Thomas Kurtz at Dartmouth College purchased a Royal McBee LGP-30 computer around 1959, which was programmed by undergraduates in assembly language.
[citation needed] In 1962, Kemeny and Kurtz submitted a proposal for the development of a new time-sharing system to NSF (which was ultimately funded in 1964).
[4] They had sufficient assurance that both Dartmouth and NSF would support the system that they signed a contract with GE and began preliminary work in 1963, before the proposal was funded.
This two-processor approach was unorthodox, and Kemeny later recalled:[6] "At that time, many experts at GE and elsewhere, tried to convince us that the route of the two-computer solution was wasteful and inefficient."
Its implementation began in 1963, by a student team[7] under the direction of Kemeny and Kurtz with the aim of providing easy access to computing facilities for all members of the college.
Two students, John McGeachie and Michael Busch, wrote the operating systems for the DATANET-30 and GE-225; Kemeny contributed the BASIC compiler.
The executive system permits simultaneous use of the card equipment, the tape drives, and the high-speed printer during time-sharing through interrupt processing.
[13] Many of its users thus believed that their terminal was the computer[14] and that, Kemeny wrote, "the machine is there just to serve him and that he has complete control of the entire system".
This method of editing provided a simple and easy to use service that allowed large numbers of teleprinters as the terminal units for the Dartmouth Timesharing system.
[18] From December 1964 into January 1965, two Dartmouth students installed working copies of DTSS and BASIC on GE computers in Phoenix.
[20] In parallel with this work, Dartmouth embarked in 1967 on the development of Phase II under the direction of Professor John Kemeny, with programming carried out by students and faculty.
The 635 version provided interactive time-sharing to up to nearly 300 simultaneous users in the 1970s, a very large number at the time, and operated at eleven commercial and academic sites in the US, Canada and Europe.
They significantly antedated Unix pipes, as design documents put their conceptual origin sometime in 1967,[28] and were described briefly in a 1969 conference: Communication files supported read, write and close operations, but also synchronous and asynchronous data transfer, random access, status inquiries, out-of-band signaling, error reporting, and access control, with the precise semantics of each operation determined by the master process.
They arranged for the second trimester of the freshman mathematics class to include a requirement for writing and debugging four Dartmouth BASIC programs.
[39] 27% of DTSS use as of 1971[update] was for casual use and entertainment, which the university stated "is in no sense regarded as frivolous", as such was an enjoyable way for users to become familiar with and not fear the computer.
[38] Kiewit's location near Dartmouth College Greek organizations made it popular for socializing;[32] students often brought dates to the Computation Center, both to play games and to demonstrate their own programs.
[15] The system allowed email-type messages to be passed between users and real-time chat via a precursor to the Unix talk program.
[38] Because BASIC did not change, the system remained compatible with older applications; Kemeny reported in 1974 that programs he had written in 1964 would still run.
