Name at birth: Melville Louis Kossuth DeweyMelvil Dewey is the founder of the library categorization method now known as Dewey Decimal Classification, or more simply the Dewey Decimal System. While working as a librarian at Amherst College, Melvil Dewey developed a system of book classification which divided nonfiction books into 10 broad categories. In Dewey's system, books were labeled and ordered on shelves by topic, using numbers from 000-999. The section 500-599, for instance, was for natural science, while 900-999 was for history and biography. Dewey's system was a hit. By the time of his death, the system was being used in over 96% of all American libraries. (In recent years, the competing Library of Congress categorization system has also become popular.) Dewey helped found the American Library Association and is credited with creating the world's first library science curriculum.
Melvil Dewey also founded the Spelling Reform Association, which was devoted to simplified English spellings: loj to replace lodge, for instance, or butr for butter. He preferred to spell his name Melvil Dui.