A Chronology of Digital Computing Machines (to 1952)

A Chronology...		The Jargon File		Computer Dictionary
Feb 1951 Ferranti Ltd., of Manchester, England, completes the first commercial computer, also called the "Mark I". 8 of them are sold. Mar 1951 Eckert and Mauchly, having sold their company to Remington Rand, complete the first UNIVAC, which is the first US commercial computer. It has 1000 12-digit words of ultrasonic memory and can do 8333 additions or 555 multiplications per second; it contains 5000 tubes and covers 200 square feet of floor. 1951 Grace Murray Hopper (1906-), of Remington Rand, invents the modern concept of the compiler. 1951-52 The EDVAC is finally completed. It has 4000 tubes, 10000 crystal diodes, and 1024 44-bit words of ultrasonic memory. Its clock speed is 1 mHz. 1952 The IBM "Defense Calculator", later renamed the "701", the first IBM computer unless you count the SSEC, enters production at Poughkeepsie, New York. (The first one is delivered in March 1953; 19 are sold altogether. The memory is electrostatic and has 4096 36-bit words; it does 2200 multiplications per second.) 1952 Grace Murray Hopper implements the first compiler, the "A-0". (As with "computer", this is a somewhat arbitrary designation.)