Wireless Sensor Networks (WSNs) are intended for monitoring an environment by sensing it, then collecting data, processing it and finally transmitting it to final destination. These sensor nodes have some constraints due to their limited energy, storage capacity and computing power. Data are routed from one node to other using different routing protocols. There are a number of routing protocols for wireless sensor networks. The authors know that the energy possessed by a node is limited and frequent communication between nodes may cause the nodes to deplete there energy resources quickly. Therefore, they need appropriate routing protocols.