Can somebody give me a hint where to find a bit of info about 'Fellowships'? There seems to be no explanation anywhere (well or I didn't find it).

I understand that you go into a fellowship to play team tournaments, but what else is the point?
- can you be in multiple fellowships?
- if so, what happens if they play each other?
- how do you get to play if a fellowship has 100 members and the tournament only 5 games? Random?
- why are fellowships so eager to get new members (I got >10 invites the day I became a member)
- and most important: how do I choose the right fellowship for me?

Thanks for any enlightenment.