...What are the mechanisms behind stop-and-go traffic? Why are there several different kinds of congestion, and how are they related? Why do most traffic jams occur considerably before the road capacity is reached?...

This paper treats an interesting multidisciplinary subject with plenty of fundamental scientific challenges, practical applications, and implications for many other fields. It gives a comprehensive overview of 50 years of traffic theory, integrating the approaches of physicists and traffic scientists. It provides a detailed review of the empirical observations and complex self-organization phenomena discovered in traffic systems as well as the theoretical methods developed to describe various kinds of driven many-particle systems.

Although traffic involves human behavior, concepts from statistical physics and non-linear dynamics have been very successful in discovering and explaining dynamical phenomena in traffic flows. Many of these phenomena are based on mechanisms such as delayed adaptation to changing conditions and the competition for limited resources, which are relevant for other systems as well. This includes pattern formation such as segregation in driven granular media and lane formation in colloid physics or biological physics (pedestrians, ants). Other examples are clogging phenomena at bottlenecks in freeway traffic, panicking pedestrian crowds, or granular media. Recently, analogies with socio-economic systems become obvious as well. For example, the so-called "slower-is-faster effect'' known from panicking pedestrian crowds has been successfully applied to the optimization of production systems. Moreover, scientists have suggested that the theory of traffic dynamics, particularly of stop-and-go waves, may also have implications for the stability and management of supply chains or for the dynamics of business cycles.