MIT Project MAC began in 1963, with funding from the US Department of Defense Advanced Research Projects Agency. One of its goals was to build an advanced time-sharing system named Multics. The Multics project used MIT's CTSS time-sharing system as a development tool. See also the 1990 Turing Award Winner, Fernando J. Corbató.
Other people in the Bell Laboratories included Peter Neumann, Joseph Ossanna, Doug McIlroy, Robert M Morris, Rudd Canaday, Brian Kernighan, Victor Vyssotsky, Douglas Eastwood.
The BCPL language was designed at Cambridge University in 1966 by Martin Richards. It is a typeless block-structured imperative language that allows programs to access memory without checking. BCPL was designed to be easily portable to multiple system environments. Project MAC memo MAC-M-352 describes the language and its first compiler implementation.
GECOS was a batch processing system for the General Electric GE-600 line of mainframe computers. Bell Laboratories and MIT used GECOS to support Multics development and debugging.
The PDP-7 was introduced by Digital Equipment in 1964. About 100 were made; the machine had 4K of 18-bit words and cost $72,000.
In 1970, Digital Equipment introduced the PDP-11 minicomputer, which had a 16-bit word size and an architecture that made adding new devices simple. It became very popular; hundreds of thousands were shipped before production ended in 1997.
Ken Thompson and Dennis Ritchie (seated) working at the PDP-11.
An oral interview was done in 2005 by John Mashey for the Computer History Museum. They describe the subject matter as including: Bell Laboratories; Unix operating system; Condon, Joe; Belle. A transcript of that interview can be found here.
Princeton provides a transcript of an interview with Ken Thompson from September 6, 1989 here.