As military systems moved onto computers at the end of the 1950s, they needed software for a kind of work the existing languages did not target. This was not scientific calculation or business record-keeping. It was real-time command and control: tracking, deciding, and responding while events unfold. JOVIAL was built for that work, and it is an early, clear case of a domain pulling a language into existence to fit its own needs.
The idea
When a domain’s needs do not fit the general languages of the day, the domain grows its own. Real-time military command and control grew JOVIAL.
Built at System Development Corporation
Starting in 1959, a team at System Development Corporation headed by Jules Schwartz created JOVIAL, a high-order language based on ALGOL 58. A high-order language let programmers write command-and-control logic in structured statements rather than in machine code, which mattered enormously for systems too large and too long-lived to maintain by hand.
Made for military systems
Through the 1960s and 1970s JOVIAL was a major systems-programming language for U.S. military command-and-control and real-time work. Roughly 95 percent of the SACCS command-and-control system was written in it, and it ran on Air Force aircraft including the B-52, the F-15, and the F-16. For decades, a great deal of the software flying and coordinating American military systems was JOVIAL.
The lesson
When a domain’s needs do not fit the general languages of the day, the domain grows its own. Here the needs were real-time response and the reliability demanded of weapons systems, and the answer was a language tuned for systems programming in that world. The pattern, a specialized domain producing a specialized language, repeats across computing history, and JOVIAL is one of its early military instances.
Related Notes
- History and Genealogy of Languages, where JOVIAL sits in the family
- SAGE and Real-Time Systems, the kind of command-and-control work this served
- Compilation vs Interpretation, how a high-order language reaches the machine
- Computing and the U.S. Military, the cluster index
Sources
- “JOVIAL,” Wikipedia. https://en.wikipedia.org/wiki/JOVIAL . Supports JOVIAL as a high-order language begun in 1959 by Jules Schwartz’s team at System Development Corporation, based on ALGOL 58, its use as a major military systems-programming language through the 1960s and 1970s, the figure that about 95 percent of the SACCS system was written in it, and its use on Air Force aircraft including the B-52, F-15, and F-16.