  Pentaquarks, namely baryons made by 4 quarks and one antiquark have been
predicted and searched for since several decades without success. Theoretical
and experimental advances in the last 2 years led to the observation of a
number of pentaquark candidates. We review the experimental evidence for
pentaquarks as well as their non-observations by some experiments, and discuss
to which extend these sometimes contradicting informations may lead to a
consistent picture.
