Non-members are players who do not pay to access extra features on Club Penguin.
Newbies: Newbie non-members are brand-new to the game. They typically wear the new player hat, Card-Jitsu pendant, a recent background, and the newest pin.
Oldies: Oldies are non-members that have been around CP for a long time (to the point where they're rare). They have very old non-member items, pins, and backgrounds.
Past Members: Non-member penguins who have been members in the past. They may or may not wear member clothes from the last time they were a member. These penguins can be recognized if they have member items or member puffles.