Category theory has become increasingly important and popular in computer science, and many universities now have introductions to category theory as part of their courses for undergraduate computer scientists. The author is a respected category theorist and has based this textbook on a course given over the last few years at the University of Sydney. The theory is developed in a straightforward way, and is enriched with many examples from computer science. Thus this book meets the needs of undergradute computer scientists, and yet retains a level of mathematical correctness that will broaden its appeal to include students of mathematics new to category theory.

"Nice, crisp introduction to category theory, motivated by examples and use in computer science. Mathematical sophistication blends nicely with fundamental concepts and examples to make the connections (and usefulness) understandable to good undergraduates." The American Mathematical Monthly

"Within the setting of distributive categories, nicely explained here, one sees data structure abstractions done properly. The example of queues is the most compelling in that all of the structure of distributive categories is used....strongly recommend[ed].David B. Benson, Computing Reviews

"...probably the clearest introduction to category theory written to date." The Bulletin of Mathematics Books