ABSTRACT
This chapter provides a brief review of the modeling of currents in
classical physics. A good understanding of currents is essential in
any attempt to make the connection between new nanoelectronic
devices and a suitable circuit description. In the sections, the
various currents are defined precisely and approximations aremade
explicitly. Although in theory, currents express the conservation of
charge, the conservation of energy and its consequences for the
theory of circuits are discussed, too.
