  This paper reviews recent developments in the theory of the quantum Hall
effect (QHE) in the magnetic-field-induced spin-density-wave (FISDW) state of
the quasi-one-dimensional organic conductors (TMTSF)$_2$X. The origin and the
basic features of the FISDW are reviewed. The QHE in the pinned FISDW state is
derived in several simple, transparent ways, including the edge states
formulation of the problem. The temperature dependence of the Hall conductivity
is found to be the same as the temperature dependence of the Fr\"ohlich
current. It is shown that, when the FISDW is free to move, it produces an
additional contribution to the Hall conductivity that nullifies the total Hall
effect. The paper is written on mathematically simple level, emphasizes
physical meaning over sophisticated mathematical technique, and uses inductive,
rather than deductive, reasoning.
