  Measurements of heavy flavor production in heavy-ion collisions have played
an important role in understanding the properties of the quark-gluon plasma
created in such collision. Due to their large masses, heavy flavor quarks
present unique sensitivity to the kinematics as well as the dynamics of the hot
and dense medium. In this article, a selection of recent measurements on heavy
flavor production in p+p, p+A and A+A collisions at both RHIC and LHC energies
will be presented. The measurements in p+p collisions serve as benchmarks to
fundamental theories, and as references to similar studies in A+A collisions
where the hot medium effects are present. On the other hand, the measurements
in p+A collisions can help to quantify the cold nuclear matter effects which
are also in effect in A+A collisions and thus need to be taken into account
when interpreting the measurements in heavy-ion collisions. The experimental
results from A+A collisions are discussed and compared to theoretical
calculations, which can shed lights on the understanding of the quark-gluon
plasma.
