"This textbook presents a useful introduction to basic category theory, and would be suitable for a first course at the undergraduate level in computer science or mathematics."
Steve Awodey, Mathematical Reviews
A crystal clear introduction to category theory that demystifies functors, natural transformations, limits and colimits, adjunctions and more. Any beginning postgraduate mathematician will find all they need in this excellent text to access the subject. Over 200 exercises are provided with solutions available online.