Cloud Computing is a textbook designed for the undergraduate computer science and information technology students of all Indian universities for an introductory course on the subject. Beginning with the origin of the subject and also the major factors influencing and shaping the very discipline, the book details upon the architecture, models, cloud data center, virtualization concepts both at the system and network level. Infrastructure, security and platforms which are considered central to the subject have been discussed as separate chapters. The last chapter of the book is devoted to the futuristic trends outlining topics such as application specific cloud computing, groupware cloud, T-Systems and Comet Cloud.