1.1 From Mechanical Calculators to Commercial Computers
(Compiled from [Brader www], [Franksen 1965], [Hed 1963], Press Release of ENIAC, Febr 15,1946)Mechanical Computers
The earliest contributions to mechanical calculation are represented by Wilhelm Schickard's machine for automatic addition,subtraction, and partly multiplication in 1623, Blaise Pascal's addition machine in 1645, many similar efforts during 1674-1820 ending with the first mass produced calculator, Tomas de Colmar's Arithmometer, and Charles Babbage's difference engine, for solving mathematical problems including simple differential equations in 1822.The Hollerith Machine and Punched Card Computing Systems
The first invention inspired by the Babbage machine, that had a substantial impact on the automation of computing was the electro-mechanical Hollerith machine which was developed in the 1890s for rapid handling of census results. These machines were initially just counting machines working with punched cards but were early provided with the ability to make additions. The use of punched cards had earlier been used by Babbage, who had taken the idea from Jacquard. From 1924 on the Hollerith machines were called IBM machines.During the 1920's and 1930's punched card systems developed steadily and were used widely in the USA and Europe for large administrative applications. In this way a natural need for efficient automatic computing developed which paved the way for computers.
The first Hollerith machine in Finland was installed in 1923 at the Statistics Office. In 1955 there were about 80 punched card computing systems in use in Finland.
Electro-mechanical Computers
In the late 1930s the German engineer Konrad Zuse was designing electro-mechanical computers Z1 (mechanical), Z2 and Z3. The Z3, finished in 1941, was probably the first programmable computer. It was a floating point binary machine with a 64 word store. All these computers were destroyed as a result of the bombing of Berlin during the Second World War, only Z4, the first of his machines using electronic tubes and finished in 1945, survived. Zuse's work did not become known outside Germany until after the end of the war.