Donald E. Knuth is, in his own words on his Stanford home page, “Professor Emeritus of The Art of Computer Programming at Stanford University.” He is one of the most influential figures in computer science, best known for the multi-volume book series that gave him that unusual title.
His central work is The Art of Computer Programming (TAOCP), a comprehensive treatment of algorithms and the mathematics needed to analyze them. He began the project in the early 1960s, and the series has grown to several volumes over the following decades, with new material still appearing as fascicles. Knuth’s home page notes that at the end of 1999 the books were named among the best twelve physical-science monographs of the century by American Scientist, alongside works by Dirac, Einstein, and Feynman.
Knuth is also remembered for tools he built when existing ones fell short. Frustrated with the typesetting of his own books, he created the TeX typesetting system, which remains a standard for mathematical and scientific publishing. Alongside it he developed literate programming, an approach that treats a program as a document meant to be read by humans as well as executed by machines.
For these contributions, especially his rigorous analysis of algorithms, Knuth received the ACM Turing Award in 1974. His insistence that algorithms be studied with mathematical precision, rather than judged only by whether they run, is a large part of why the analysis of algorithms is a discipline today.