A-0 System: Meaning (information, definition, explanation, facts)

The A-0 system, written by Grace Hopper in 1951 and 1952 for the UNIVAC I, was the first compiler ever developed for a electronic computer.^[1] The A-0 functioned more as a loader or linker than the modern notion of a compiler. A program was specified as a sequence of subroutines and arguments. The subroutines were identified by a numeric code and the arguments to the subroutines were written directly after each subroutine code. The A-0 system converted the specification into machine code that could be fed into the computer a second time to execute the program.

The A-0 system was followed by the A-1, A-2, A-3 (released as ARITH-MATIC), AT-3 (released as MATH-MATIC) and B-0 (released as FLOW-MATIC).

Notes

1. ↑ Hopper "Keynote Address", Sammet pg. 12

References

1. Hopper, Grace. "The Education of a Computer". Proceedings of the Association for Computing Machinery Conference (Pittsburgh) May 1952. 
2. Hopper, Grace. "Automatic Coding for Digital Computers". High Speed Computer Conference (Louisiana State University) February 1995, Remington Rand. 
3. Hopper, Grace. "Keynote Address". Proceedings of the ACM SIGPLAN History of Programming Languages (HOPL) conference. 
4. Ridgway, Richard E.. "Compiling Routines". Proceedings of the 1952 ACM national meeting (Toronto) ACM '52. 
5. Sammet, Jean (1969). Programming Languages: History and Fundamentals. Prentice-Hall, pg. 12.