Ken Thompson and Dennis Ritchie Explain UNIX (Bell Labs)

Segment from an AT&T Bell Labs (BTL) promotional film (circa 1980s) featuring UNIX creators Ken Thompson and Dennis Ritchie briefly explaining the UNIX environment. In cameo roles you’ll see UNIX luminaries Greg Chesson (in the wine red shirt) and Doug McIlroy (to the foreground of Greg). Also featured is a classic ASR-33 Teletype, BLIT displays (developed by Rob Pike, then of the Labs as well), and much more.