QCD

These lecture notes are directed at a level suitable for graduate students in High Energy Physics. They are intended to give an introduction to the theory and phenomenology of quantum chromodynamics (QCD), focusing on colliderphysics applications. The aim is to bring the reader to a level where informed decisions can be made concerning different approaches and their uncertainties. The material is divided into five main areas: (1) fundamentals, (2) fixedorder perturbative QCD, (3) Monte Carlo event generators and parton showers, (4) Matching at Leading and Next-to-Leading Order, and (5) Soft QCD physics.