Yep. Unix was written on a PDP-7 http://www.linfo.org/pdp-7.html http://www.linfo.org/pdp-7.html -- probably with 8,000 or 16,000 words of memory (18 bit words)

Yep. Unix was written on a PDP-7 http://www.linfo.org/pdp-7.html http://www.linfo.org/pdp-7.html -- probably with 8,000 or 16,000 words of memory (18 bit words), probably running on the order of several thousand instructions per second