CASOC

CASOC was an early ENIAC program developed in the mid-1940s for the Moore School of Electrical Engineering and the U.S. Army’s Ballistics Research Laboratory (BRL). It is historically noted as one of the first programs run on ENIAC, a milestone in the transition from manual calculation to automated computation. The program was designed to generate artillery firing tables and perform ballistic trajectory calculations.

Origin and development: CASOC was created by teams working at BRL and the Moore School, with programming carried out by some of ENIAC’s pioneering programmers. The effort involved the group frequently named the ENIAC Six: Jean Jennings Bartik, Frances Spence, Kathleen Antonelli, Marlyn Wescoff, Ruth Lichterman, and Betty Holberton. Because ENIAC was not a stored-program computer, CASOC was implemented through manual wiring, plugboards, and a sequence of decimal arithmetic operations, arranged to execute a predefined set of steps for each calculation.

Purpose and operation: The program computed the complex numerical work required to produce artillery firing tables, solving differential equations and carrying out large-scale numerical calculations. It demonstrated that automated computation could produce accurate results far more quickly than manual methods, though it required substantial setup time and physical reconfiguration to handle different problems.

Significance and legacy: CASOC is frequently cited as the first program executed on ENIAC, illustrating the early shift toward programmable computation and setting the stage for subsequent software development in the field. The work contributed to the broader history of computing by showing how programmable machines could tackle practical scientific and military calculations, even before the advent of stored-program architectures.