To know all about the badges, just click on BADGES at the top. The ones in color are the ones you got. The ones in black and white are the ones you can have, move the cursor over them to know what to do to get it.
Badges are a kind of reward-fidelity, but they do not bring any extra winnings or bonuses.
Also, if you are careful, on the profile pictures of MadWin members, on the upper left corner, there is a number, it indicates the number of badges obtained by the member.
