Source : Free On-Line Dictionary of Computing

EXEC 2
     
        1.  A {scripting language} produced by {IBM} in the
        late 1970s.
     
        Superseded by {REXX}.
     
        [SC24-5219, "Virtual Machine/System Product EXEC 2
        Reference"].
     
        [Successor to {EXEC 1}?  With or without a space?]
     
        2.  An archaic {operating system} from
        {UNIVAC}.  By about 1980 it had been replaced by {EXEC 8}.
     
        [Dates?  Did EXEC 3 to EXEC 7 exist?]
     
        (2000-08-06)