The term 'blockbuster' originally had nothing to do with movies; it was WWII military slang for a bomb large enough to destroy an entire city block. It began appearing in movie advertisements in the 1940s and 50s to describe high-budget hits, but it wasn't solidified as a genre until Steven Spielberg's 'Jaws' (1975). Before 'Jaws,' studios released big movies in only a few theaters at a time. 'Jaws' was the first to use 'wide release' (opening in hundreds of theaters simultaneously) backed by massive TV advertising. It became the first film to earn $100 million at the box office, forever changing the Hollywood business model from year-round steady releases to a hunt for the 'summer blockbuster' that dominates the market.