Combinatorics is that part of mathematics that involves counting. It is therefore a fundamental part of math, and mastering it gives you wide reaching powers. The applications of combinatorics include: probability, cryptography, error correcting, games, music, and visual art. It can help you understand other parts of math from a more fundamental perspective.
The book begins with the basics of what is needed to solve combinatorics problems, including: definitions, a guide (or classification system) for solving problems based on the twelvefold way, as well as an overview of combinatorics.
The remainder of the book consists of problems and solutions. There are 2 separate groups of problems in this book. The first group consists of 82 problems, while the second group has another 124 problems (called exercises). Each group of problems begins with the easiest ones that anyone can solve and progresses to greater difficulty.
This book is good preparation for more advanced combinatorics texts such as Lovasz's Combinatorial Problems and Exercises.