In the fractional quantum Hall effect, the Hall conductance is quantized. In the most common manifestation of the effect, which was first observed in the two‐dimensional electron gas sandwiched between the semiconducting layers of a GaAs‐AlGaAs heterostructure, the magnetic field dependence of the Hall resistance shows an ascending‐staircase‐type behavior with increasing field strength. The steps in the staircase correspond to Hall conductance values of the form(p/q)e2/h,and they occur around the magnetic field values for which the number of electrons per magnetic field quantum isp/q,withpandqintegers andqusually odd.