John Boyd was a United States Air Force fighter pilot and military strategist, known for his innovative theories on air combat and military strategy. He developed the OODA Loop, a decision-making process that stands for Observe, Orient, Decide, and Act, which has influenced both military and business strategies. Boyd was also a key figure in the development of the F-16 Fighting Falcon and played a significant role in shaping modern air combat tactics. His ideas challenged conventional military thinking and emphasized agility and adaptability in warfare, making him a controversial yet respected figure in military circles.