A Wireless Sensor Network (WSN) is composed of a thousand spatially distributed devices like a sensor node (mote) to sensing physical conditions such as temperature, pressure etc. and then it sends the sensed data to the distinct location through the network. Sensor nodes are resource constrained so lifetime of network is important issue. There are different routing protocols that have been proposed for this issue. Routing protocols are described for efficiently use energy of sensor nodes (motes. Energy efficiency and network lifetime are the primary issues in WSNs.