2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/53384Fractional superstrings are non-trivial generalizations of ordinary superstrings and heterotic strings, and have critical spacetime dimensions which are less than ten by virtue of a worldsheet fractional supersymmetry relating worldsheet bosons to worldsheet parafermions. In this paper, I provide a short non-technical survey of the fundamental issues involved in these recently-proposed theories. After introducing the basic ideas which underlie these new string theories, I review their early successes and outline some related outstanding questions. ( Talk given at the Internal Workshop on String Theory, Quantum Gravity, and the Unification of the Fundamental Interactions, held in Rome, Italy, 21-26 September 1992. )15 pages (LaTeX), McGill/92-42High Energy Physics - TheoryFractional Superstrings with Critical Spacetime Dimensions Four and Six: A Status Reporttext