Think of a club like a clubhouse at your local course. With clubs you can add as many events as you want. For example you could add a weekly women's league, a Friday skins game, a member guest tournament and a club championship. You can also manage all the members at a club including their registration details, make announcements, notify members of upcoming events and allow members to see the results of all the events.
To create a club first open the Groups tab on the home screen -> tap the Clubs tab at the top -> tap the green + button.