Object detection in videos has increased its popularity because of its wider applications. It has gained more research attention now days as it is applicable in real time situations like pedestrian detection, anomaly detection, Self moving cars, sports, counting of people etc. This paper begins with the introduction of object detection and briefs the basic steps in the process. It also provides a review of various techniques and approaches used for object detection in videos. Discussion of every approach and limitations will provide several promising directions and guidelines for future work.