(Standards Eastern Automatic Computer) The first electronic computer that executed an internally stored program. Created by the U.S. National Bureau of Standards (see NIST), SEAC was placed into operation in 1950. Using solid-state diodes for logic, SEAC was an arithmetic-only device with 512 45-bit words of delay line memory. Based on the EDVAC SEAC was based on the Electronic Discrete Variable Automatic Computer (EDVAC), the successor to the ENIAC. Although EDVAC was also a stored program computer, it became operational after SEAC. See EDVAC, ENIAC, early memories and early computers.