Technology 1920-1930

1921 robot, fax

1922 insulin, 3-D movie

1923 frozen foods

1924 loud speaker, spiral notebooks

1925 mechanical television

1926 liquid fueled rockets

1927 electronic television, Technicolor

1928 penicillin, woman's’ vote equal to mans’ vote

Sources:http://inventors.about.com/od/timelines/a/twentieth.htm

Saettler, P. (2004). The Evolution of American Educational Technology. Greenwich, CT: Information Age Publishing

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