Claude Shannon

Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American 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 the first to describe the use of Boolean algebra—essential to all digital electronic circuits—and helped found artificial intelligence (AI). Roboticist Rodney Brooks declared Shannon the 20th century engineer who contributed the most to 21st century technologies, and mathematician Solomon W. Golomb described his intellectual achievement as "one of the greatest of the twentieth century".

At the University of Michigan, Shannon dual-degreed, graduating with a Bachelor of Science in electrical engineering and another in mathematics, both in 1936. As a 21-year-old master's degree student in electrical engineering at MIT, his 1937 thesis, "A Symbolic Analysis of Relay and Switching Circuits", 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in 1940 with a PhD in mathematics; his thesis focusing on genetics contained important results, while initially going unpublished.

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".

His 1948 paper "A Mathematical Theory of Communication" laid the foundations for the field of information theory, referred to as a "blueprint for the digital era" by electrical engineer Robert G. Gallager and "the Magna Carta of the Information Age" by Scientific American. Golomb compared Shannon's influence on the digital age to that which "the inventor of the alphabet has had on literature". Advancements across multiple scientific disciplines utilized Shannon's theory—including the invention of the compact disc, the development of the Internet, the commercialization of mobile telephony, and the understanding of black holes. He also formally introduced the term "bit", and was a co-inventor of both pulse-code modulation and the first wearable computer. He also invented the signal-flow graph.

Shannon made numerous contributions to the field of artificial intelligence, including co-organizing the 1956 Dartmouth workshop considered to be the discipline's founding event, and papers on the programming of chess computers. His Theseus machine was the first electrical device to learn by trial and error, being one of the first examples of artificial intelligence.

The Shannon family lived in Gaylord, Michigan, and Claude was born in a hospital in nearby Petoskey. His father, Claude Sr. (1862–1934), was a businessman and, for a while, a judge of probate in Gaylord. His mother, Mabel Wolf Shannon (1880–1945), was a language teacher, who also served as the principal of Gaylord High School. Claude Sr. was a descendant of New Jersey settlers, while Mabel was a child of German immigrants. Shannon's family was active in their Methodist Church during his youth.

Most of the first 16 years of Shannon's life were spent in Gaylord, where he attended public school, graduating from Gaylord High School in 1932. Shannon showed an inclination towards mechanical and electrical things. His best subjects were science and mathematics. At home, he constructed such devices as models of planes, a radio-controlled model boat and a barbed-wire telegraph system to a friend's house a half-mile away. While growing up, he also worked as a messenger for the Western Union company.