Majorana modes in hybrid nanowires are effectively chargeless, zero-energy quasiparticles. They have recently attracted strong interest, both as exotic quasi-particles and as candidates for topological quantum computing. They arise from the splitting, through a phase transition, of bulk electronic states into pairs of quasiparticles on the wire ends, each one being its own antiparticle. Several experiments with hybrid superconductor-semiconductor nanowires using tunneling spectroscopy from a normal conductor to the nanowire have observed a zero bias peak consistent with a Majorana state. In this talk, I will summarize the results obtained for my doctoral thesis so far. These results range from the Majorana phases in 1D smooth junctions and finite nanowires to 2D nanowires with planar and cylindrical geometries. Their physics regarding electrical transport and optical absorption properties will be also presented. References: [1] J. Osca and L. Serra, arXiv:1501.06710v1 (2015). [2] D. Ruiz, J. Osca and L. Serra, J. Phys.: Condens. Matter 27 125302 (2015). [3] J. Osca, D. Ruiz and L. Serra, Phys. Rev. B, 89, 245405 (2014). [4] J. Osca, R. López, and L. Serra, Eur. Phys. J. B, 87, 84 (2014). [5] J. Osca and L. Serra, Phys. Rev. B, 88, 144512 (2013).