The inventor of "Liquid Paper" or as we may know it, "White-Out" was Betty Nesmith Graham. Graham got an idea she'd seen done by sign painters, which was to add another layer of paint to cover-up mistakes. She used a kitchen blender to mix-up her first batch of substance to cover-up over mistakes made on paper at work. After much experimenting and then being fired for spending so much time distributing her product as a trial, she received a patent in 1958. Wow!