RWH may refer to: Rainwater harvesting Random walk hypothesis Red wine headache a bad headache that occurs in many people after drinking even a single glass of red wine Revolutionary Workers Headquarters, a U.S. Marxist-Leninist organization that formed out of a split from the Revolutionary Communist Party (RCP) in 1977 Ridley–Watkins–Hilsum theory Real World Haskell, a book about the Haskell programming language