IBM 3790 was a computer system developed by the IBM Data Processing Division (DPD) announced in 1975, one of the first distributed computing platforms. It preceded the IBM 8100, announced in 1979.
It was designed to be installed in branch offices, stores, subsidiaries, etc., and to be connected to the central host mainframe, using IBM Systems Network Architecture (SNA).
Read more about IBM 3790: Components, Host Software, Lack of Marketing Success