How Dennis Ritchie and Ken Thompson wrote Unix
CTSS
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Multics on GE-645
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Bell Labs leaves Multics
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GECOS on GE-635 as bootstrap host
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PDP-7 target machine
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Teletype Model 33 ASR used for input/output
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paper tape bootstrap
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early Unix on PDP-7
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Unix becomes self-hosting
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PDP-11 Unix
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Unix rewritten in C
