This book covers the essentials of computer science and Information Technology – from history of computing to developments in the Internet, e-mail, www, multimedia, virtual reality and so on. An indispensable textbook for all introductory courses in computer science. Covers the syllabi of various courses including BCA, B.Sc. (Computer Science), BE, PGDCA, IGNOU, ICWAI, ICAI, MBA, DOEACC, and so on. Equally suitable for general readers wanting to have an in-depth knowledge of computing fundamentals.