Computers

June 21, 1948

The first program on the world’s first stored-program computer, the Manchester Small-Scale Experimental Machine (SSEM) is run. This first program was designed to test the computer’s reliability and ran for 52 minutes performing 3.5 million operations.

June 20, 1950

The National Bureau of Standards dedicated the SEAC (Standards Eastern Automatic Computer) in Washington. The SEAC was the first computer to use all-diode logic, a technology more reliable than vacuum tubes, and was the first stored-program computer completed in the United States. Magnetic tape in the external storage units stored programming information, coded subroutines, numerical data, and output.

June 15, 1911

The Computing – Tabulating – Recording Co. (C-T-R), a consolidation of the Computing Scale Co. of America, The Tabulating Machine Co., and The International Time Recording Co. is incorporated in New York. In 1924, C-T-R adopted the name International Business Machines, better known as IBM.

June 14, 1822

In a paper to the Royal Astronomical Society, Charles Babbage unveils his design for a machine he called the Difference Engine, the first example of a mechanical computing machine. The British government funded the building of a Difference Engine, which Babbage never actually completed. However, Babbage’s design for the Difference Engine and his later Analytical Engine spurred future designs of working mechanical computers. In 1991 a working Difference Engine was constructed using Babbage’s plans, proving that his designs would have worked.