GeezerVison

Short Code was one of the first higher-level languages developed for an electronic computer.^[1] Unlike machine code, Short Code statements represented mathematic expressions rather than a machine instruction. Also known as automatic programming, the source code was not compiled but executed through an interpreter to simplify the programming process. The execution time was, naturally, much slower.^[2]

Short Code was proposed by John Mauchly in 1949 and originally known as Brief Code. William Schmitt implemented a version of Brief Code in 1949 for the BINAC computer, though it was never debugged and tested. The following year Schmitt implemented a new version of Brief Code for the UNIVAC I, where it was now known as Short Code (also Short Order Code). A revised version of Short Code was developed in 1952 for the Univac II by A. B. Tonik and J. R. Logan.^[3]

While Short Code represented expressions, the representation itself was not direct and required a process of manual conversion. Elements of an expression were represented by two-character codes and then divided into 6-code groups in order to conform to the 12-byte words used by BINAC and Univac computers.^[4] For example, the expression

 a = (b + c) / b * c

was converted to Short Code by a sequence of substitutions and a final regrouping:

 X3 =  (  X1 +  Y1 )  /  X1 * Y1   substitute variables
 X3 03 09 X1 07 Y1 02 04 X1   Y1   substitute operators and parentheses. 
                                   Note that multiplication is
                                   represented by juxtaposition.

 07Y10204X1Y1                      group into 12-byte words.
 0000X30309X1

Along with basic arithmetic, Short Code allowed for branching and calls to a library of functions. The language was interpreted and ran about 50 times slower than machine code.^[5]

• History of programming languages
• Algorithm

• Wexelblat, Richard L. (Ed.) (1981). History of Programming Languages, p. 9. New York: Academic Press. ISBN 0-12-745040-8
• "Short Code". hopl.info. Retrieved 2018-05-20.