Line outs occur when the ball has gone out of play and consist of a minimum of 2 players. One player throws the rugby ball back into play from the touchline. Two lines of opposing players then leap from the ground to try and catch the ball. Players can be lifted off the ground to catch the rugby ball.
Rucks and mauls can be confusing for new players. Simply put, a ruck happens when the ball is in contact with the ground. Players then try to gain an advantage by pushing their opposing players back.
The difference between rucks and mauls is the way the rugby ball is handled. During mauls the ball is off the ground. Referees can decide who gained the advantage and potentially award a scrum if there is a minor offence.
Scrums are used to restart play after any sort of rules infringement in rugby union. 8 players from each team will line up to compete in the scrum.