When Club Penguin gets 1 year older, they throw a huge party all around the island. Every year, they give away a party hat. Each year the color of the party hat changes. Here is a list describing each party hat so far:

Beta Hat:

The Beta Hat is the rarest Club Penguin Anniversary hat of all. You could only access this item if you tested Club Penguin while it was in beta phase. The Club Penguin Beta Hat is pink and yellow. It was given away as a free item in the Town on October 2005.

1st Anniversary Hat:

The 1st Anniversary Hat is green and dark blue. If you wear the 1st Anniversary Hat, people will consider you as a rare penguin. You could access the 1st Anniversary Hat in the Coffee Shop on October 2006.

2nd Anniversary Hat:

The 2nd Anniversary is yellow and orange. If you wear the 2nd Anniversary hat, people will consider you as medium rare. You could access the 2nd Anniversary Hat in the Book Room on October 2007.

3rd Anniversary Hat:

The 3rd Anniversary Hat was blue, yellow, and orange. If you wear the 3nd Anniversary Hat, it shows you were around on Club Penguin in 2008. You could access the 3rd Anniversary Hat at the Coffee Shop on October 2008.

4th Anniversary Hat:

The 4th Anniversary Hat was purple and blue. If you wear the 4th Anniversary hat, it shows you were around on Club Penguin in 2009. You could access the 4th Anniversary Hat in the Coffee Shop on October 2009.