|Similar creatures||Ostrich, other flightless birds|
|Predators||Whales and leopard seals (not seen in Club Penguin)|
ID numbers of penguins
All penguins in Club Penguin had ID numbers starting with the letter P, for example, P123456789. Their names would be displayed as this string of numbers until approved by Club Penguin Staff. The ID number also signifies how old a penguin is, as the smaller the number is, the earlier the penguin was created (for example, if a penguin's ID was P1375918 then they would be the 1,374,918th penguin created on Club Penguin). Names were usually approved per-language, so a penguin with an approved name on English servers could still display as P(numbers) on Spanish servers, even if the account was created years prior.
In Club Penguin Island, unapproved names displayed as CP(ten digit number). It is unknown if these numbers had any correlation to any aspect of the account, or were simply random. Since the release of Offline Mode on December 21, 2018, penguin names no longer have to be approved.
The earliest known penguins are caveguins, also known as cave penguins. They lived in the prehistoric era of the island with dinosaurs. There, they worked, lived, and played. The caveguins had a more limited vocabulary than the present-day penguins. Due to the Prehistoric Party 2013, many caveguins were confused about penguins coming from the 'strange shiny thing', known as the Time Trekker. They then discovered that they were from the present. The only named caveguin is Garugg the Ugg Ugg.
- Main article: Food and Drinks
- After the release of the new Buddy List, player's friends now have a green circle around them in-game.
- Penguins on Club Penguin are exactly 3.5 feet tall, as shown by the Mug Shot Background.
- Main article: Color