2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/96531Presented is an overview of electromagnetic versions of the so-called X-type waves intensively studied since their invention in early 1990.-ies in ultrasonics. These waves may be extremely localized both laterally and longitudinally and - what has been considered as most startling - propagate superluminally without apparent spread. Spotlighted are the issues of the relativistic causality, variety of mathematical description and possibilities of practical applications of the waves.16 pages, 4 figures. To be published in Proc. of Intern. Conf."Time's Arrows, Quantum Measurements and Superluminal Behaviour," (held in Naples, October 2-6, 2000) to be issued by the Italian NCROpticsGeneral Physicstext