Michigan Terminal System

MTS is an operating system for IBM System/360 and its successors that was developed jointly by the following institutions:

• University of Michigan
• Wayne State University[?]
• Simon Fraser University
• University of Alberta
• University of British Columbia

(others)

Popular programs developed for MTS include MAD, FORMAT and CONFER.

MTS doesn't implement directories, but there is a de facto two-tier grouping of files owing to the inclusion in a file's name of its owner's four-character MTS callsign.