The long experiences of teaching in post-graduate Department and interaction with cross section of students, in fact, inspired us to take up the challenge of writing a comprehensive book only on photosynthesis. The present book, entitled "Photosynthesis" is an attempt to bring out a comprehensive book with an array of information, starting from classical/ fundamental to recent developments. However, photosynthesis is such a subject where large numbers of research activities are under way and new progress is made frequently. So, sincere efforts have been made by authors to gift this book to students as a full package, encompassing all recent and update information about the photosynthesis. The book comprises many chapters, such as Introduction, Light reaction, Dark Reaction, Photorespiration/ Glycolate Metabolism (C2-Cycle), Bacterial Photosynthesis and Factors Affecting the Rate of Photosynthesis. Each chapter is very comprehensive and has been highly simplified to give clarity to the text  and concept to be easily comprehensible through; lucid language, suitable headings and sub-heading, illustrative diagrams, flow chart, cycles, graphs and tables. The chapter Bacterial Photosynthesis is well described, which is otherwise not getting much attention in most of the available books. In the last section selected references have been given and small list of valuable books have also been suggested for the benefit of students.