Did you know that a paper proofreader was invented by a woman. Beth Graham, after her divorce in 1951, was forced to take a job as a typist to support herself and her son. She made a lot of mistakes during her work and began to correct them by covering them up with white tempera paint. Using her kitchen and garage as a laboratory, she experimented with the components of the corrector to improve its quality. Beth soon offered her invention, the Error Corrector, to IBM, but they refused.
Not discouraged by the setback, Beth Graham changed the product name to Liquid Paper and set up production in her garage. She sold her proofreader for 17 years until, in 1979, Gillette Corporation paid $ 47.5 million for the patent buyback, plus a percentage of sales.