Introduction to Abstract Algebra, Second Edition presents abstract algebra as the main tool underlying discrete mathematics. This edition offers numerous updates based on feedback from first edition adopters, as well as improved and simplified proofs of a number of important theorems. Many new exercises have been added throughout, while new study projects examine skewfields, quaternions, and octonions. Each chapter includes exercises of varying levels of difficulty, chapter notes that point out variations in notation and approach, and study projects that cover an array of applications.