GRAVITATIONAL MICROLENSING

Foundations of standard microlensing theory are discussesd as applied to stars in the Galactic bulge, Magellanic Clouds or other nearby gala xies and gravitational microlenses assumed to lie in-between these sta rs and the terrestrial observer. In contrast to the review article by Gurevich et al. [48], microlensing by compact objects is mainly consid ered. Criteria for the identification of microlensing events are discu ssed as also are microlensing events not satisfying these criteria, su ch as non-symmetrical light curves and chromatic and polarization effe cts. Large Magellanic Cloud (LMC) and Galactic bulge microlensing data of the MACHO group are discussed in detail and also LMC data of EROS and Galactic bulge data of OGLE are presented. A detailed comparison o f theoretical predictions and observations is given.