  Open charm hadrons are excellent probe to study the dynamics of quarks and
gluons inside hadrons. Because the mass of a charm quark is heavier than
$\Lambda_{QCD}$, the so called heavy quark symmetry emerges in the hadron
containing a charm quark and plays a central role in the classification and
constraining the interactions. Belle and BaBar, which are B-factory
experiments, have made significant advances in the field of open charm hadron
spectroscopy in these 15 years. In this article, experimental advances on both
open charm mesons and baryons by B-factory experiments are reviewed. Finally,
the prospect of the open charm hadrons with the next generation B-factory
experiment, Belle II is described.
