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A-0 System 1

A-0 System

The A-0 system (Arithmetic Language version 0), written by Grace Hopper in 1951 and 1952 for the UNIVAC I,

was the first compiler ever developed for an 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 said 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).

The A-2 system was developed at the UNIVAC division of Remington Rand in 1953 and released to customers by

the end of that year. Customers were provided the source code for A-2 and invited to send their improvements back

to UNIVAC. Thus A-2 was an early, and perhaps the first, example of free and open-source software.

External links Proceedings of the 1954 MIT Summer Session on "Digital Computers - Advanced Coding Techniques, section 7 -

A2 Compiler and Associated Routines for use with Univac[2]

Notes

[1][1] Hopper "Keynote Address", Sammet pg. 12

[2] http:/ /bitsavers.informatik. uni-stuttgart.de/pdf/mit/summer_session_1954/

Digital_Computers_Advanced_Coding_Techniques_Summer_1954. pdf

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 1955. 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. pp. g. 12.

http://bitsavers.informatik.uni-stuttgart.de/pdf/mit/summer_session_1954/Digital_Computers_Advanced_Coding_Techniques_Summer_1954.pdfhttp://bitsavers.informatik.uni-stuttgart.de/pdf/mit/summer_session_1954/Digital_Computers_Advanced_Coding_Techniques_Summer_1954.pdfhttp://bitsavers.informatik.uni-stuttgart.de/pdf/mit/summer_session_1954/Digital_Computers_Advanced_Coding_Techniques_Summer_1954.pdfhttp://en.wikipedia.org/w/index.php?title=Free_and_open-source_softwarehttp://en.wikipedia.org/w/index.php?title=UNIVAChttp://en.wikipedia.org/w/index.php?title=FLOW-MATIChttp://en.wikipedia.org/w/index.php?title=MATH-MATIChttp://en.wikipedia.org/w/index.php?title=ARITH-MATIChttp://en.wikipedia.org/w/index.php?title=Machine_codehttp://en.wikipedia.org/w/index.php?title=Linker_%28computing%29http://en.wikipedia.org/w/index.php?title=Loader_%28computing%29http://en.wikipedia.org/w/index.php?title=Compilerhttp://en.wikipedia.org/w/index.php?title=UNIVAC_Ihttp://en.wikipedia.org/w/index.php?title=Grace_Hopper

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Article Sources and Contributors 2

Article Sources and ContributorsA-0 System Source: http://en.wikipedia.org/w/index.php?oldid=585254795 Contributors: Abcarter, Amine Brikci N, Bluhd, CRGreathouse, Danakil, Danim, Derek Ross, DmitTrix, Ellmist,

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