  Repeating and apparently non-repeating Fast Radio Bursts are distinct classes
of events produced by distinct classes of sources. As for conference
proceedings, this paper reviews the evidence for that division, and then
discusses the statistics of and possible models of each class of source: black
hole accretion discs for repeating FRB and hypermagnetized neutron stars (SGR)
for apparently non-repeating FRB. An added appendix suggests a cutoff frequency
of coherent emission that is consistent with these models and with known PSR.
