John Archibald Wheeler was an influential American theoretical physicist known for his work in nuclear physics and general relativity. He played a significant role in the development of the atomic bomb during World War II as part of the Manhattan Project. Later, he contributed to the understanding of black holes and coined the term "black hole" itself. Wheeler also introduced the concept of "it from bit," suggesting that information is fundamental to the universe. He mentored many prominent physicists, including Richard Feynman and Kip Thorne, and was a professor at Princeton University for several decades.