Phenomenology of hard diffraction at high energies

We present some of the topics covered in two lectures under the same title that were given at the "Summer School on High Energy Physics at the LHC: New trends in HEP" in Natal, Brazil. In this contribution we give a brief review on the application of perturbative QCD to the hard diffractive processes. Some examples of phenomenology for the diffractive production of $W/Z$, heavy $Q\bar{Q}$ and quarkonium in hadron-hadron reactions are presented. It is also discussed the exclusive diffractive processes in $ep$ interactions. They are in general driven by the gluon content of proton which is strongly subject to parton saturation effects in the very high energy limit. These saturation effects are well described within the color dipole formalism. We present some examples of corresponding phenomenology as the elastic vector meson production and the DVCS relying on the color dipole approach.