An agent is a software and/or hardware entity with four special features which are: Reactive, Proactive, Autonomous and Social. A System in which Multiple agents when collaborate with each other to achieve some common goal or objective is called Multiagent System. If an agent along with four essential features has one more feature of learning then agent is considered intelligent agent. Agents may use any various techniques from the field of Artificial intelligence, mathematics and operation research to fulfill their objectives. This paper will highlight various techniques used by agents in Multiagent System along with various applications of Multiagent Systems.