Descriptive Geometry Language. Early CAD/CAE language,
used light pen. "Interactive Graphic Consoles - Environment
and Software", R.L. Beckermeyer, Proc FJCC 37 (1970).
Data General ca 1973-1974. Derivative of ALGOL 60,
developed from DG's ALGOL-5, used as the systems language
for the DG Eclipse family of computers.
Replaced by PL/I in the early 80's. Data General manual