An ad-hoc routing protocol is a caucus, or customary, that controls how nodes decide which way to route packets between computing devices in a mobile ad hoc network. Over the years, abundant routing protocols have been developed for ad hoc mobile networks. These can be categorized into table-driven and on-demand routing. The simulations have shown that there certainly is a need for a special ad-hoc routing protocol when mobility increases and security in mobile ad-hoc networks is an extensive area of research. This research paper is a compassing of research on ad-hoc routing protocols. It gives a sufficient amount of literature for the better understanding of the work ahead.