Abstract: Optical Character Recognition (OCR) is a technology that provides a full alphanumeric recognition of printed or handwritten characters. Optical Character Recognition is one of the most interesting and challenging research areas in the field of Image processing. Image Acquisition, Pre-processing, Segmentation, Feature Extraction and Classification are stages of OCR. In this paper, how character patterns are identified in the classification stage by different algorithms is presented. Template Matching Algorithm, statistical Algorithm, Structural Algorithm, Neural Network Algorithm and Support Vector Machine Algorithm are presented in this paper.