2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/47804A brief review is presented of selected topics, including a world-sheet formulation of M theory, couplings and scales in M phenomenology, the perils of baryon decay and the possible elevation of free-fermion models to true M- or F-theory compactifications.10 pages, no figures, Talk presented at the Workshop on Phenomenological Applications of String Theories, ICTP, Trieste, October 1997High Energy Physics - Phenomenologytext