John Danaher is a renowned Brazilian Jiu-Jitsu (BJJ) instructor and practitioner, known for his expertise in grappling and submission techniques. He has trained many successful athletes, including Gordon Ryan and Gary Tonon, and is recognized for his analytical approach to teaching. Danaher is also a black belt under Renzo Gracie, a prominent figure in the BJJ community. In addition to his teaching, Danaher has gained popularity through his instructional videos and online courses, which cover various aspects of BJJ. His unique perspective on strategy and technique has influenced many practitioners and contributed to the growth of the sport worldwide.