We do not follow the historical development of the quark model and the group-theoretical discussion of flavor symmetry, as most textbooks do. Instead,we begin in the first section with the introduction of the color charge of quarks and a detailed discussion of the associated symmetry group. The second section examines the dynamics of the strong interaction through the exchange of gluons. The cross sections of all simple reactions involving quarks and gluons are derived. The third section follows with a treatment of the hadron spectrum in the quark model. The fourth section examines hadronic decays due to the electromagnetic and strong interactions of the constituents. In the fifth section, the discovery of long-lived massive hadrons and their explanation as bound states of new heavy quarks is discussed. This experimental discovery has significantly contributed to the development of the Standard Model. The discovery of the top quark in 1995 marked another milestone in this development.