Membership is when you pay Club Penguin and you get special features.
An average membership penguin
Badges[]
1 to 6 Month Badge (lowest). It is extremely common.
7 to 12 Month Badge. Many penguins have this badge.
13 to 18 Month Badge. It is not seen as much as the previous badges.
19 to 24 Month Badge. it is quite uncommon to see this.
25+ months Badge. Many old penguins and all moderators and characters have this badge.