This book presents original research results on pseudodifferential operators.C*-algebras generated by pseudodifferential operators with piecewise smooth symbols on a smooth manifold are considered. For each algebra, all the equivalence classes of irreducible representations are listed; as a consequence, a criterion for a pseudodifferential operator to be Fredholm is stated, the topology on the spectrum is described, and a solving series is constructed.Pseudodifferential operators on manifolds with edges are introduced, their properties are considered in details, and an algebra generated by...