The landscape of homological algebra has evolved over the last half-century into a fundamental tool for the working mathematician. This book provides a unified

Homological algebra, because of its fundamental nature, is relevant to many branches of pure mathematics, including number theory, geometry, group theory and ri

First Published in 2018. This book grew out of a course of lectures given to third year undergraduates at Oxford University and it has the modest aim of produci

Homological algebra first arose as a language for describing topological prospects of geometrical objects. As with every successful language it quickly expanded

In this chapter we are largely influenced in our choice of material by the demands of the rest of the book. However, we take the view that this is an opportunit