The book is designed to give an insight of the art and science of Information Technology for those who desire to improve their way of working and does not expect any comprehend the subject matter. the book is divided into fourteen chapters and different facets of Information Technology is discussed in each chapter. The book covers hardware, software, programming languages, operating system as well as binary and other number systems used in digital computers and also discusses computer networks, Internet, World Wide Web, Windows 98, viruses and email. Most of these topics are included in the curriculum of the first year study of BCA, B.E. courses in Computer Science, Electronics and Communication Engineering as well as in M.Tech, MCA, AMIE, IETE, GNIIT Courses and also in Diploma courses conducted by Technical Board of Education.