Source : Free On-Line Dictionary of Computing

Edinburgh Multi Access System
     
         (EMAS) One of the first {operating systems}
        written in a {high-level language} ({IMProved Mercury
        autocode}), apparently predating {Unix}.
     
        [Papers in J. {British Computer Society}].
     
        [More info?  Dates?]
     
        (1996-04-07)