Superconductivity is one of the most important macroscopic quantum coherent phenomena in physics, where at sufficiently low temperature electrons form Cooper pairs sharing the same phase. When an interface is realized between a superconductor (S) and a normal (N) material, a phenomenon called Andreev reflection occurs: an electron impinging from the normal side towards the interface cannot penetrate the superconductor as a single quasiparticle and is back-reflected as a hole. Recently, one of the most interesting and studied setups involving a normal and a superconducting material is the case of semiconductor nanowires with spin-orbit coupling (SOC), where a nanowire portion, covered by a superconducting film, acquires a superconducting pairing by proximity effect.