# Dewey Decimal System
Invented by [[Melvil Dewey]] in 1870s. Used in libraries all around the world.
Uses decimal numbers to designate specific categories/genres:
- 000: Computer science, information, and general
- 100: Philosophy and psychology
- 200: Religion
- 300: Social sciences, sociology, law, etc
- 400: Languages and linguistics
- 500: Science-related
- 600: Technology
- 700: Arts
- 800: Literature and languages
- 900: History and geography
Reference: https://www.youtube.com/watch?v=xHiL5ZviQhQ