With the advent of smart devices and the Internet, data is being generated from various sources including mobile phones, sensor networks, telecommunications, satellites, log data, business, health care and many government sectors where the data is likely to arrive with speed. Data which flows continuously with respect to time is called streaming data and detection anomaly in such data in real time is an open challenge. Detecting anomaly in right time facilitates the appropriate control actions for the anomaly in right time. There are several techniques for detecting anomaly. In this paper, an overview of different techniques for detection of anomaly is presented.