Melvil Dewey, born in 1851, devised a system that is used by most schools and libraries for organizing books.  Called the Dewey Decimal System (DDC),  it divides books into ten broad catagories. The DDC is the world's most widely used library classification system.

	000-099	General works (encyclopedias and similar works)
	100-199	Philosophy (how people think and what they believe)
	200-299	Religion (including mythology)
	300-399	Social Sciences (folklore, legends, government, manners and customs, vocations)
	400-499	Language (dictionaries, grammars)
	500-599	Pure Science (mathematics, astronomy, chemistry, nature study)
	600-699	Technology (applied sciences - aviation, building, engineering, homemaking)
	700-799	The Arts (photography, drawing, painting, music, sports)
	800-899	Literature (plays, poetry)
	900-999	Geography & History (ancient and modern, travel)

Learn more about the Dewey Decimal System classifications from the Online Computer Library Center.