Eric Steven Raymond (born December 4, 1957), often referred to as ESR, is an American software developer, author of the widely cited 1997 essay and 1999 book The Cathedral and the Bazaar and other works, and open-source software advocate. He wrote a guidebook for the Roguelike game NetHack. In the 1990s, he edited and updated the Jargon File, currently in print as The New Hacker's Dictionary.
Raymond was born in Boston, Massachusetts, in 1957 and lived in Venezuela as a child. His family moved to Pennsylvania in 1971. He has suffered from cerebral palsy since birth; his weakened physical condition motivated him to go into computing.