This book introduces the concepts of diverse programming languages for students who have already mastered basic programming in at least one language. It is suitable for use in an undergraduate course for computer science and computer engineering majors. It treats all the knowledge units in the area of programming languages that appear in the ACM's Computer Science Curriculum 2008, and introduces the core units thoroughly. It gives programming exercises in three different language paradigms. Philosophically, it is in complete agreement with the ACM report.