The ENIAC

In 1942, John Maauchy, a physicist for the US Army, proposed an all electronic calculating machine to calculate a complex ballistics tables. Other than Army use, it was also used to solve numerical problems through reprogramming. It was called the ENIAC, or teh Electronic Numberical Integrator and Computer, and it was introduced in 1946. The ENIAC used vacuum cubes inside of it, since transistors were not invented yet, and used a total of 17500 cubes in total. It was the worlds first fully electronic computer, which meant it wasn't limited by any mechanical parts, and it was the first general-use computer. It precedes all modern computers.