Claude Shannon

Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American polymath who was a mathematician, electrical engineer, computer scientist, cryptographer, and inventor known as the "father of information theory", and the man who laid the foundations of the Information Age.

Shannon was among the first to describe the use of Boolean algebra—essential to all digital electronic circuits—and helped found the field of artificial intelligence. The roboticist Rodney Brooks declared Shannon the 20th century engineer who contributed the most to 21st century technologies, and the mathematician Solomon W. Golomb described his intellectual achievement as "one of the greatest of the twentieth century".

At the University of Michigan, Shannon graduated with Bachelor of Science degrees in electrical engineering and mathematics, both in 1936. The following year, in his MIT electrical engineering master's thesis "A Symbolic Analysis of Relay and Switching Circuits", he demonstrated that electrical applications of Boolean algebra could construct any logical numerical relationship, thereby establishing the theory behind digital computing and digital circuits. Called by some the most important master's thesis of all time, it is the "birth certificate of the digital revolution", and started him in a lifetime of work that led him to win a Kyoto Prize in 1985. He graduated from MIT in 1940 with a PhD in mathematics; his thesis, which focused on genetics, contained important results though it remained unpublished and relatively unknown until recently.

Shannon contributed to the field of cryptanalysis for national defense of the United States during World War II, including his fundamental work on codebreaking and secure telecommunications, writing a paper which is considered one of the foundational pieces of modern cryptography, with his work described as "a turning point, and marked the closure of classical cryptography and the beginning of modern cryptography". His work was foundational for symmetric-key cryptography, including the work of Horst Feistel, the Data Encryption Standard (DES), and the Advanced Encryption Standard (AES). As a result, Shannon has been called the "founding father of modern cryptography".