Lindy Hop evolved in the early 1930s. It is a dance of African-American origin characterized by a high degree of physical vigor. It is characterized by an 8-count basic, the "swingout", that transitions from an open position through a closed position and back. It has an emphasis on improvisation and the ability to include other steps in 8-count and 6-count rhythms. The name "Lindy Hop" is often attributed to "Shorty" George Snowden during an interaction with a newspaper writer who asked him what kind of dance they were doing.

Source: Wikipedia