A Very Short Introduction to Topos Theory (adapted from Prof. Pettigrew's notes)

Abstract

A quick overview of category theory and topos theory including slice categories, monics, epics, isos, diagrams, cones, cocones, limits, colimits, products and coproducts, pushouts and pullbacks, equalizers and coequalizers, initial and terminal objects, exponential objects, subobjects, subobject classifiers, the definition of a topos, algebras of subobjects, functors, natural transformations and adjoint functors. This paper is refashioned and adopted from Richard Pettigrew's university notes.