Miscellaneous
The default ITS top-level command interpreter was the PDP-10 machine language debugger (DDT). The usual text editor on ITS was TECO and later Emacs, which was written in TECO. Both DDT and TECO were implemented through simple dispatch tables on single-letter commands, and thus had no true syntax.
The Jargon File started as a combined effort between people on the ITS machines at MIT and at SAIL.
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