Asymmetric exclusion processes (ASEP) have attracted much attention due to their rich
and complex dynamic phase behaviors. This formalism describes particles hopping
with hard-core repulsion along a 1D lattice. Such systems provide a good description of
traffic flow, the kinetics of biopolymerization, polymer dynamics in dense media,
diffusion through membrane channels, dynamics of motor proteins moving along
rigid filaments, etc. On the one hand, ASEP can be solved exactly under certain
circumstances. On the other hand, despite their simplicity, ASEP and related
models show a range of nontrivial macroscopic phenomena, such as boundary induced
phase transitions, spontaneous symmetry breaking, and phase separation.

In this presentation, the basic concepts and various nonequilibrium phenomena of the ASEP
will be introduced. In particular, the generalization of ASEP to networks will be highlighted.