  In 2007, a very bright radio pulse was identified in the archival data of the
Parkes Telescope in Australia, marking the beginning of a new research branch
in astrophysics. In 2013, this kind of millisecond bursts with extremely high
brightness temperature takes a unified name, fast radio burst (FRB). Over the
first few years, FRBs seemed very mysterious because the sample of known events
was limited. With the improvement of instruments over the last five years,
hundreds of new FRBs have been discovered. The field is now undergoing a
revolution and understanding of FRB has rapidly increased as new observational
data increasingly accumulates. In this review, we will summarize the basic
physics of FRBs and discuss the current research progress in this area. We have
tried to cover a wide range of FRB topics, including the observational
property, propagation effect, population study, radiation mechanism, source
model, and application in cosmology. A framework based on the latest
observational facts is now under construction. In the near future, this
exciting field is expected to make significant breakthroughs.
