Whitfield Diffie is an American cryptographer known for his pioneering work in public-key cryptography. Born on January 5, 1944, he co-invented the Diffie-Hellman key exchange method in 1976, which allows two parties to securely share a secret key over an insecure channel. This innovation laid the groundwork for modern secure communications. Diffie's contributions to cryptography have had a profound impact on computer security and privacy. He has received numerous awards for his work, including the Turing Award in 2015. His research continues to influence the fields of information security and encryption technology.