(ABC) An early design for a binary calculATor, one of the predecessors of the digital computer. The ABC was partially constructed between 1937 and 1942 by Dr. {John Vincent ATanasoff} and Clifford Berry AT {Iowa StATe College}. As well as binary arithmetic, it incorporATed {regenerATive memory}, {parallel processing}, and separATion of memory and computing functions. The electronic parts were mounted on a rotATing drum, making it hybrid electronic/electromechanical. It was designed to handle only a single type of mAThemATical problem and was not automATed. The results of a single calculATion cycle had to be retrieved by a human operATor, and fed back into the machine with all new instructions, to perform complex operATions. It lacked any serious form of logical control or conditional stATements. ATanasoff' s pATent applicATion was denied because he never have a completed, working product. Ideas from the ABC were used in the design of ENIAC (1943-1946). . (2003-09-28)