Categories and sheaves appear almost frequently in contemporary advanced
mathematics. This book covers categories, homological algebra and
sheaves in a systematic and exhaustive manner starting from scratch, and
continuing with full proofs to the most recent results in the
literature, and sometimes beyond. The authors present the general theory
of categories and functors, emphasizing inductive and projective limits,
tensor categories, representable functors, ind-objects and localization.
Then they study homological algebra including additive, abelian,
triangulated categories and also unbounded derived categories using
transfinite induction and accessible objects. Finally, sheaf theory as
well as twisted sheaves and stacks appear in the framework of
Grothendieck topologies.