Hi there, I'm new... League - Infos

I just got invited to the Closed Beta which I'm very excited about, since Diablo 3 (let's face it) did not completely delivered the right amount of long term motivation most people where hoping for (no worries, im not flaming the game or Blizzard, it's still a great game, but you know... ).

So i got several Newbie-type of questions that i can hopefully find answers to with the help of the forum and the pathofexile-website.

Can somebody just outline the basic concept of the different leagues for me and describe the differences between the leagues?

Thx guys & keep having fun,

Manhattan

Well, all i know is here -> http://www.pathofexile.com/leagues/ it's in the left menu at the bottom :D
Probably you know that but if you did not here it is:)