Q:
A: The main difference is what happens when the play stops. In league, when there's a tackle, the game is stopped and restarted, in union they play on. In league, they don't have line outs or scrums, the attacking team gets the possession, whereas in union both teams can compete for the ball. Basically the difference is with the forwards, in union they are there to gain possession of the ball, in league, they are just bigger versions of the backs.