A Textbook on Automata Theory has been designed for students of computer science. Adopting a comprehensive approach to the subject, the book presents various concepts with adequate explanations. The logical and structured treatment of the subject promotes better understanding and assimilation. Lucid and well-structured presentation makes the book user-friendly. The book cover the curricula for M.C.A., B.E.(Computer Science) and M.Sc. (Computer Science) at various universities and gives students a strong foundation for advanced studies in the field.Key features:-• A wide array of solved examples and applications• Numerous illustrations supporting theoretical inputs• Exercises at the end of each chapter for practice• Notation for describing machine models• A brief history of mathematicians and computer scientists