The authors review the various string models proposed to describe hadrons and their interactions. QCD and QCD-inspired phenomenological models motivated the development of a rather large variety of string models. Among others the Polyakov model, the Friedberg-Lee model, the MIT flux tube model, semirelativistic string models of hadrons and massive strings are discussed in detail. To correctly describe the dynamical aspects of the hadron-hadron interaction, especially of high-energy heavy-ion collisions, ideas from these models are proposed to be combined into a semiclassical unified string-flux tube model. Special emphasis is given to the dynamical string model recently developed on the basis of such a unified string-flux tube model.