The book sets forth both the classical results of knot theory and the famous and remarkable latest ideas of recent years, leading to the rapid development of this theory (Jones, Kaufman polynomial, HOMFLY, Kontsevich integral, Bar-Nathan theory, braid theory, Markov's theorem, Deornois algorithm, virtual knot theory). Separately, the author's approach to various problems of knot theory, based on the concept of a d-diagram, is presented.