"A Mathematical Theory of Communication" is an article by mathematician Claude E. Shannon published in Bell System Technical Journal in 1948.

[1][2][3][4] It was renamed The Mathematical Theory of Communication in the 1949 book of the same name,[5] a small but significant title change after realizing the generality of this work.

[10] The paper also formally introduced the term "bit" and serves as its theoretical foundation.

The book contains an additional article by Warren Weaver, providing an overview of the theory for a more general audience.

Shannon's article laid out the basic elements of communication: It also developed the concepts of information entropy, redundancy and the source coding theorem, and introduced the term bit (which Shannon credited to John Tukey) as a unit of information.