The scrums define the forwards. A scrum is a set piece with all the forwards bound together. Details on the scrum can be found on a separate page.
The scrumhalf puts the ball straight into the space between the two front rows (the tunnel). By combining a driving push and a quick foot strike by the hooker (occasionally a prop) each team attempts to win the ball. It is then channeled back to the #8 who lets it out to the scrumhalf (who has moved to the back) or breaks off and picks it up. The team who gets to put the ball in has the advanta ges of timing and having their front row closer to the put-in point. By driving forward we not only win the ball, but give momentum to any subsequent offensive moves after the ball is out.
Here is a example of a post-tackle ruck. In these scenes, the tackled player is about to place and release the ball. Her teammate sees the yellow player close to the ball, and she decides to ruck instead of picking up the ball. A ruck can clear the yellow player off the ball, and protect the red player from being tackled when she tries to pick up the ball. Both players get down low and try to drive the other player off the ball. The scrumhalf (#9) waits behind the play until the ball is clear, picks the ball up, and passes it to the backs to continue the game.
A maul occurs when a player in possession is in contact with a defender while they are both on their feet and one or more offensive players join the contact situation. One way to think of a maul is that it is a ruck, but standing up.
Mauls begin to be formed when a player carrying the ball comes into contact with a player on the opposite team, but does not get tackled. Instead, they remain standing, and try to protect the ball. The other team will be trying to "strip" or "rip" the ball out of the ball carrier's hands. Upon contact, the ball carrier hits the opposing player hard, turns around, and drives backwards. The initial hit is to create space and keep her momentum moving towards her goal line. The ball carrier turns around to protect the ball from being taken by the other team. She drives backwards to continue moving in the right direction.
The ball carrier calls for her team to help her, by yelling that she has the ball, and wants another player on her team to strip it out of her hands. The next offensive player to the breakdown strips the ball out of her hands, using her elbow and body weight to force the ball down and out of the ball carrier's hands. At this point, the maul is officially formed.
Once she has the ball, she turns and begins driving backwards as well. She has now insulated the ball from the other team, and is helping move the entire play towards her goal line. She can either pass the ball out to the scrumhalf (#9), hold on to the ball and continue driving, or strip away from the maul and run with the ball.
In a real maul, there are many other players bound into the play as well. They either bind on low and drive the formation down the pitch, or they try to strip or steal the ball from the other team. Mauls are extremely tiring if they longer than a few seconds.