Computer History By 18vaswanin2 Jun 14, 1822 Difference Engine Period: Jun 14, 1822 to Oct 7, 2014 Technology Oct 7, 1831 Telegraphy Mar 7, 1876 Telephone Oct 6, 1887 Calculator Oct 7, 1929 Tape Recorder Oct 7, 2014 First US earth satellite launched
