Pickup
Show up and play, informal, spontaneous soccer games where players are assigned teams on the day. It's a casual way to play the game, with no referees and players managing the games between them. The focus is on fun and socializing, with games often varying in size and format.
Leagues/Tournaments
Sign up and play for a period, usually a couple of months. These are still somewhat informal but require commitment over a specific period. These leagues are still casual, but you get consistent playing with the same players over the season. It's a great way to get to know new folks