In November 1976, Whitfield Diffie and Martin E. Hellman published "New Directions in Cryptography" in IEEE Transactions on Information Theory -- a paper that revolutionized the field by introducing the concept of public-key cryptography and the first practical key exchange protocol. Their breakthrough made it possible for two parties to establish a shared secret over an insecure channel without prior communication. This foundational work underpins virtually all modern secure communication, including SSL/TLS, SSH, and critically, the elliptic curve cryptography that secures every Bitcoin transaction.
Read their 1976 paper titled "New Directions in Cryptography"
here.