That is a penguin, usually called "Tux" (for the Tuxedo they are supposed to appear to be wearing.
Mandriva (used to be Mandrake) dress their penguin in a Tuxedo to look like Mandrake the magician, and Gentoo even name their distribution after a species of Penguin.
The original idea came from Linus Torvalds, the prime mover behind Linux.
