Neutrinos are the only known elementary particles that are Majorana fermion candidates, implying that they would be their own antiparticles. The most sensitive and perhaps only practical probe of the Majorana nature of neutrinos is an extremely rare nuclear decay process, the double beta decay without the emission of neutrinos. After an introduction to the physics of neutrinoless double beta decay, I will present the main experimental techniques to search for this exceedingly rare process. I will show the latest results from leading experiments in the field, then discuss future projects and their prospects to probe the inverted neutrino mass ordering scenario.