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ITS - Incompatible Timesharing System

ITS is a timesharing system created at MIT's Artificial Intelligence Laboratory in 1967 for their PDP-6 computer. It was soon moved to the newer PDP-10; for most of its life ITS ran on four of those machines. ITS is known for it's lack of security (no passwords, no file permissions), using a debugger as the login shell, and pioneering many famous programs.

The SDF ITS is at and is running on a KA10 emulator with an attached PDP-11 for serving Knight TV raster graphics terminals.

Some basic tutorials:

More information can be found by running INFO, and on GitHub.

Bootcamp ideas:

  • Log in and create your own user directory. Hint: see “basic tutorials” above.
  • Run :INFO INFO to learn how to read the system documentation. Read “INTRO” to learn some ITS basics. List all the files in the INFO directory.
  • Create a file using EMACS. Hint1 :INFO EMACS. Hint2 :TEACHEMACS.
  • Start several jobs in parallel and switch between them. Hint1: ^Z. Hint2: $J. Hint3: $P. Hint4: $$V.
  • Write, compile, link, and run a small C program. Hint1: .INFO.; CC RECENT. Hint2: C; CDOC >
  • Learn PDP-10 programming with :INFO PDP-10. Do one of the examples. Hint :INFO MIDAS
  • Get 50 points in Zork. Hint1: ZORK^K. Hint2: score.
  • Compute the derivative and integral of an expression in Macsyma. Hint1: :MACSYMA
  • Write a function in Maclisp to print “hello world”. Hint1: LISP^K. Hint2: :INFO LISP.
  • Learn about Lisp from the automated tutor: :teach;lisp.

Suggested topics to explore:

  • Zork and Advent, classic text adventure games.
  • Emacs, the first version.
  • Maclisp and Scheme, major Lisp dialects.
  • Macsyma, symbolic math.
  • Logo, programming for kids.
  • C, pre-K&R version.
  • Muddle, the Dynamic Modeling programming language.
  • Maze, the 3D first person shooter (needs an Imlac emulator).
its.txt · Last modified: 2023/08/31 06:26 by larsb