I see. I didn't know I could join mutiple guilds. Are there any benefits to it?
I believe I can't represent multiple guilds at once right? So what does representing a guild does?
Benefits of joining multiple guilds is that you aren't tied down to any particular guild. If you want to switch on the fly to play with guild X that has real life friends without leaving Guild Y, you can.
And you are correct, you cannot represent more than one guild at once. IIRC representing guild can give you certain bonuses while playing, but I'm not sure. Someone else will need to explain that.