This books is prepared on the syllabus issued by the department of electronics (DOE) and under the scheme of all India council for technical education (AICTE), department of information technology (DIT), and ministry of communication and information technology (MICT), Government of India. The book is divided into the nine chapters and each chapter strictly covers the topics as per the syllabus defined by DOEACC society. Each topic in the chapter is property explained with the help of computer snap shots, wherever necessary. At the end of each chapter, summery of the chapter is provided for quick review of it. All the chapters are covered with large no. of questions as per the guidelines of DOE. large no. of objective type questions are also provided with the answers to them. Not limited to this, proper care has taken to write the chapters in simple English and step-by-step approach is used for the easy and fast understanding purpose.