University of Pennsylvania researchers John Mauchly and J. Presper Eckert develop ENIAC and are widely credited for inventing the first digital computer. It contains 18,000 vacuum tubes, weighs 30 tons and computes 1,000 times faster than any other machine. In 1973, a judge rules that Mauchly derived ENIAC from John Vincent Atanasoff's ABC computer. The ruling invalidates ENIAC's patent and calls Atanasoff "the inventor of the first electronic computer."

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