BASE jumping, also sometimes written as B.A.S.E. jumping, is an activity where participants jump from fixed objects and use a parachute to break their fall. 'BASE' is an acronym that stands for four categories of fixed objects from which one can jump: buildings, antennas, spans (bridges), and earth (cliffs). The acronym 'B.A.S.E.' (now more commonly 'BASE') was coined by filmmaker Carl Boenish, his wife Jean Boenish, Phil Smith, and Phil Mayfield. Carl Boenish was the real catalyst behind modern BASE jumping, and in 1978, he filmed the first BASE jumps to be made using ram-air parachutes and the freefall tracking technique (from El Capitan, in Yosemite National Park). While BASE jumps had been made prior to that time, the El Capitan activity was the effective birth of what is now called BASE jumping. BASE jumping is significantly more dangerous than similar sports such as skydiving from aircraft, and is currently regarded by many as a fringe extreme sport or stunt.
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