Wireless Sensor Networks consist of small nodes with sensing and computation, communication capabilities. Wireless network is highly dependent on the specific application and are constrained by energy, storage capacity, and power. To increase the lifetime of networks, energy awareness is the essential consideration if we analyze routing protocols. Routing protocols of sensor networks are responsible for maintaining the routes in the network. In this paper, we analyze recent routing protocols for wireless sensor network and classify in three types of approaches according to network architecture in WSN. The three main categories on the basis of network structure: Flat, Hierarchical and location based routing protocols. We study the trade-off between energy and communication overhead savings in every routing protocol. We also highlighted the advantages and performance issues of each routing technique.