  Achieving a precise description of the internal structure of hadrons is a
hard task, since there are several bottlenecks to obtain theoretical
predictions starting from first principles. In order to complement the
highly-accurate experiments, it is necessary to use ingenious strategies to
impose constraints from the theory side. In this article, we describe how
photons can be used to unveil the internal structure of hadrons. Using
up-to-date PDFs and FFs, we explore how to describe NLO QCD plus LO QED
corrections to hadron plus photon production at colliders.
