Categories

Abstract

Institution-independentmodel theory as a categorical abstract model theory relies heavily on category theory. This preliminary chapter gives a brief overviewof the categorical concepts and results used by this book. The reader without enough familiarity with category theory is advised to use one of the textbooks on category theory available in the literature. [111] and [26] are among standard references for category theory. A reference for indexed categories discussing many examples from the model theory of algebraic specification is [174], while [101] contains a rather compact presentation of fibred category theory.