Based on a design by John von Neumann (then a RAND consultant) and built at RAND in 1953, the JOHNNIAC (shown here in 1955) was one of six "Princeton class" stored program machines. Like the others in its class, it was "hand built, individually adapted, and had its own peculiarities" (Gruenberger 1968). In 1955 William Orchard-Hayes and Leola Cutler implemented a linear programming package on the JOHNNIAC. Image courtesy of the RAND Archives.