2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/62806This text is a draft of the review paper on projectively dual varieties. Topics include dual varieties, Pyasetskii pairing, discriminant complexes, resultants and schemes of zeros, secant and tangential varieties, Ein theorems, applications of projective differential geometry and Mori theory to dual varieties, degree and multiplicities of discriminants, self-dual varieties, etc.review paper, 195 pagesAlgebraic Geometry14text