Donald E. Knuth's seminal publications have earned him a loyal following among scholars and computer scientists, and his award-winning textbooks have become classics that are often given credit for shaping the field of computer science. In this volume, he explains and comments on the changes he has made to his work over the last twenty years in response to new technologies and the evolving understanding of key concepts in computer science. His commentary is supplemented by a full bibliography of his works and a number of interviews with Knuth himself, which shed light on his professional life and publications as well as provide interesting biographical details. A giant in the field of computer science, Knuth has assembled materials that offer a full portrait of both the scientist and the man. The final volume of a series of his collected papers, "Companion to the Papers of Donald Knuth" is essential for the Knuth completist.