Image retrieval is a poor stepchild to other forms of information retrieval (IR). Image retrieval has been one of the most interesting and vivid research areas in the field of computer vision over the last decades. Content-Based Image Retrieval (CBIR) systems are used in order to automatically index, search, retrieve, and browse image databases. Color and texture features are important properties in content-based image retrieval systems. In this paper we have mentioned detailed classification of CBIR system. Also we have discussed about the efficiency of different techniques used in CBIR. We have compared different techniques as well as the combinations of them to improve the performance. We have also compared the effect of different matching techniques on the retrieval process.