  Primordial black holes (PBHs) represent a natural candidate for one of the
components of the dark matter (DM) in the Universe. In this review, we shall
discuss the basics of their formation, abundance and signatures. Some of their
characteristic signals are examined, such as the emission of particles due to
Hawking evaporation and the accretion of the surrounding matter, effects which
could leave an impact in the evolution of the Universe and the formation of
structures. The most relevant probes capable of constraining their masses and
population are discussed.
