A mobile ad hoc network (MANETs) is a self-organizing system of mobile nodes that communicate with each other via wireless links with no fixed infrastructure or centralized administration such as base station or access points. MANETs nodes can communicate directly if they are in each other transmission range; else the relay nodes are forwarding the packets to neighbors or receivers. This connectivity between multiple nodes is furnished by network layer. Due to the MANETs open wireless medium security is one of the indispensable roles to resist attacks such as Rushing, Black Hole, and Worm Hole etc. Among these Black Hole attack is one of the major attack and this detection and prevention is still considered as a challenging task in ad hoc networks. Therefore this paper exposes a study of Black Hole attack and its various prevention techniques that are explored recently.