The fundamental problems of ad hoc network by giving its related research background including the concept, features, status, and vulnerabilities of MANET. They also present an overview and the study of the routing protocols. Also include the several challenging issues, emerging application and the future trends of MANET. As the popularity of mobile device and wireless networks significantly increased over the past years, wireless ad-hoc networks have now become one of the most vibrant and active fields of communication and networks. In this paper review the different technology of MANET.