This book is based on the authorampamp39s 18 years of teaching and research experience.ampampnbspIt covers the fundamental principles in Computer and Internet securityampampnbspincluding software security hardware security network security web security and cryptography. ampampnbspIts goal is to help readers understand how variousampampnbspattacks work what their fundamental causes areampampnbsphow to defend against them and how various defense mechanisms work.ampampnbspThe book can be used as a textbook for undergraduate and graduateampampnbspcourses. Over 80 universities and colleges adopted the first editionampampnbspof this book within the first 15 months since it was published in late 2017.The author strongly believes in ampampquotlearning by doingampampquot soampampnbspthe book takes a handson approach.ampampnbspFor each security principle the book uses a series of handson activitiesampampnbspto help explain the principle readers can touch play with and experiment with theampampnbspprinciple instead of just reading about it.ampampnbspFor instance if a security principle involves an attackampampnbspthe book guides readers to actually launch the attack in aampampnbspcontained environment.