This book has been specifically designed and written to meet the requirements of the BE/BTech students of GTU. The use of digital electronics in increasing in all disciplines of engineering. This book will help the students to deal with the basics of digital technology, including the design aspects of circuits. Student-friendly, lucid and comprehensive, this book will be a perfect reference for engineering students of all courses in Electronics and Communication Information Technology, Computer Science, Applied Physics, Computer Software, MCA and AIEE. It will also serve as a good reference for competitive examinations.