This monograph aims at providing an introduction to key concepts,algorithms, and theoretical frameworks in Optical character recognition System. The intended readership consists of electrical engineers with a background in soft computing, machine learning,and pattern recognition. This monograph builds on first, the principles of Machine learning and organizes the main ideas of optical character recognition. For the sake of clarity, we group the various attempts into three categories (a) Printed, (b) handwritten and online character recognition. This monograph is written in the following divisions: All we need to know about character recognition is explored in introductory Ch.1 and Ch2. The generalized framework of OCR and their modules are thoroughly described in Ch3-Ch8. Status and future of OCR are discussed inCh9. Concluding remark is discussed in Ch10. Instead of giving exhaustive details on the OCR on a different script, this monograph is meant as a view point for beginners and researchers into the literature on ideal character recognition system.