A maul is formed when a ball carrier is held, but not tackled by an opponent. Players from either side are free -- from an onside position -- to bind onto other players in the maul and attempt to drive the ball carrier in one direction or another. It can be formed anywhere on the pitch, albeit it doesn't generally happen in the try zones. Once a maul has formed offside lines form at the "hindmost" foot at each end of the maul. Players seeking to join a maul must do so from behind that offside line. No one may deliberately bring down the maul. If you can get to the ball carrier you may attempt to tackle him, but you may not deliberately bring down any player who does not have the ball. You can only try to shove them backwards. In a well managed driving maul, the ball will be passed back (or ripped) to a player who has bound to the end of the maul. The players in front of him will continue to drive, pushing the opposition back and effectively shielding the ball carrier. It is one of the few situations (along with the scrum) where players may legally be in front of the ball and yet not be in a offside situation. The maul ends when (1) the maul goes down anyway and is effectively turned into a ruck or (2) when the player with the ball chooses to peel off or unbind from the maul or pass or kick the ball. Open play rules then apply.

Why don't you try out the source I have mentioned below? I'm sure there are many more similar websites, but the BBC website has video clips explaining the various rules of the game. Good luck!

Here, watch this.... it's good...