  We study the circular orbits of charged particles around a weakly charged
Kerr black hole immersed in a weak, axisymmetric magnetic field. Firstly, we
review the circular orbits of neutral particles. We then review the circular
orbits of charged particles around a weakly charged Kerr black hole and weakly
magnetized Kerr black hole. The case of a weakly magnetized and charged black
hole is investigated thereafter. We investigate, in particular, the effect of
the electromagnetic forces on the charged particles' innermost stable circular
orbits. We examine the conditions for the existence of negative-energy stable
circular orbits and the possibility of the emergence of a gap or double orbit
in thin accretion disks. Some of the interesting astrophysical consequences of
our findings are discussed as well.
