“This book offers a fast, but very complete, introduction to the basic concepts in category theory, which any reader with a basic knowledge of abstract algebra will follow easily. … The theory is very well complemented by a list of proposed exercises at the end of every chapter… . This book is appropriate, as was said previously, for a fast introduction to category theory, and could be very useful for a short introductory course on categorical methods in advanced algebra.” (Juan Antonio López-Ramos, Mathematical Reviews, July, 2017)

“This book is, as promised in this series, a compact, easy to read and useful for lecturers introduction to the basic concepts of category theory. It is very convenient for self-studying and it can be used as starting point to read more advanced book on category theory. The book includes very nice and helpful diagrams, detailed explanation of the concepts and, in every chapter, a set of exercises that will help the reader to better understanding the text.” (Blas Torrecillas, zbMATH 1360.18001, 2017)