Accumulation of theoretical experience, on one hand, and experimental data, on the other, resulted in a considerable progress in weak interactions. The current literature concentrates mainly on such issues as the study of the Kobayashi-Maskawa matrix and the application of quantum chromodynamics to concrete processes. Here I discuss the most interesting developing fields referring both to old (light) and new (heavy) hadrons. The first part is devoted to [Formula: see text] oscillations and other processes of the second order yielding information on Vbu and the t quark mass. The second and the largest part describes the modern QCD-based approaches in the traditional problems (K meson and hyperon physics) and in new problems associated with heavy quarks.
Lectures on Heavy Quarks in Quantum Chromodynamics
