Donald Knuth has made numerous contributions to mathematics and to computer science. In computer science he has been enormously influential, ranging from his advocacy of "literate programming" to his series of books on The Art of Computer Programming. The foundations said that "His enormous contributions ... have established him as a giant in the field." Knuth has also written mathematics books, ranging from Surreal Numbers, an exposition of Conway's theory of numbers and games (written in the form of a play), to Concrete Mathematics (written with Ron Graham and Oren Patashnik). People who love good typesetting and beautiful books, especially those who need to typeset mathematics, know Knuth as the author of the TeX typesetting system which has become the standard in many fields.