"Since their work was classified they couldn’t tell me what they were doing, so I had no idea what I would be doing. When finally clearance came, I was shown the ENIAC and I’ve worked in computers ever since."
EDVAC was one of the earliest electronic computers. Unlike its predecessor the ENIAC, it was binary rather than decimal, and was a stored-program computer. ENIAC inventors John Mauchly and J. Presper Eckert proposed the EDVAC's construction in August 1944. A contract to build the new computer was signed in April 1946 with an initial budget of US$100,000. EDVAC was delivered to the Ballistics Research Laboratory in August 1949. Functionally, EDVAC was a binary serial computer with automatic addition, subtraction, multiplication, programmed division and automatic checking with an ultrasonic serial memory capacity of 1,000 44-bit words. EDVAC's average addition time was 864 microseconds and its average multiplication time was 2,900 microseconds. By 1960 EDVAC was running over 20 hours a day with error-free run time averaging eight hours. EDVAC ran until 1961 when it was replaced by BRLESC. During its operational life it proved to be reliable and productive for its time.