Source : Free On-Line Dictionary of Computing

Internal Translator
     
         (IT) An early {compiler} for
        mathematics developed by A.J. {Perlis} et al at Carnegie Tech
        ca 1957.  IT was originally written for the {Burroughs 205},
        then the {IBM 650}.
     
        IT was the forerunner of RUNCIBLE, GATE, CORRELATE and GAT.
        IT source code was converted to PIT, thence to SPIT.
     
        IT-2 produced machine language directly, IT-3 developed at
        Carnegie added double-precision {floating-point}.
     
        [Sammet 1969, pp. 139-141].
     
        [CACM 1(5):22 1958].
     
        (1994-11-30)