arXiv:hep-ph/9510377v1 23 Oct 1995 Theoretical Physics Institute University of Minnesota TPI-MINN-95/31-T UMN-TH-1413-95 October, 1995 Lectures on Heavy Quarks in Quantum Chromodynamics ∗ Mikhail Shifman Theoretical Physics Institute, University of Minnesota, Minneapolis, MN 55455 Abstract A pedagogical introduction to the heavy quark theory is given. It is explained that various expansions in the inverse heavy quark mass 1/m Q present a version of the Wilson operator product expansion in QCD. A systematic approach is developed and many practically interesting problems are considered. I show how the 1/m Q expansions can be built using the background field technique and how they work in particular applications. Interplay between perturbative and nonperturbative aspects of the heavy quark theory is discussed. ∗ An extended version of the lectures given at Theoretical Advanced Study Institute QCD and Beyond, University of Colorado, Boulder, Colorado, June 1995.