The book by mathematician, chess master and writer Evgeniy Gik explores the various connections between chess, mathematics and computers. The author summarizes the results of his many years of research on two related topics - “Mathematics on the chessboard” and “Computer chess”. Different types of chess-mathematical problems and puzzles are considered. Entertaining records are presented and the geometric properties of the board and pieces are analyzed. Unusual games are described: fairy-tale, Fisher, on cylindrical boards and others. The mathematics of tournament schedules and the calculation of ratings are discussed. The author makes an excursion into the history of computer chess, talks about the world championships among programs, about matches between machines and chess kings - Kasparov and Kramnik. From this chess-mathematical “Bible” the reader will also learn about the successes of computers in analyzing endings, solving problems, etudes and puzzles.