Routing is one of the most challenging task in mobile ad hoc networks. Several works have been proposed to address this challenge. Majority numbers of researchers have introduced the routing protocols based on minimize resource consumption but still research needs improvement to design the efficient routing protocols which control the node movement. Proper use of location information and dynamically adjustment of intermediate nodes’ retransmission adopted by a number of algorithms contribute to a reduction in the number of retransmissions and consequently reduce control overhead and resource consumption, but this feat was achieved at a price on network reachability. In this paper, an overview of analytical, network, and simulation model used in the design of routing mechanisms wherever possible is presented. This review paper classifies routing protocols into three categories named as route discovery, QoS (Quality of Service), and route maintenance with their relative performance. This paper also compares routing mechanisms against routing efficiency, reliability, packet delay, packet delivery ratio, control overheads, and QoS. This paper reviewed some current literatures that were proposed to improve the reliable, resource consumption, scalable, and QoS based routing mechanisms. This article also highlights the performance demands required of these protocols to assist researcher in MANET resource conservation as a good starting point for developing efficient routing algorithm.