Tux is the official mascot of the Linux kernel. Originally created by Larry Ewing as an entry for a Linux logo competition, Tux quickly became the most widely recognized symbol of the Linux operating system.
The concept of the Linux brand character being a penguin came from Linus Torvalds, the creator of Linux. According to Torvalds, he contracted "penguinitis" after being nibbled by a penguin on a visit to the National Zoo & Aquarium in Canberra, Australia.
Linus Torvalds chose a penguin as the mascot because of his fondness for these flightless birds. Tux represents the spirit of open-source software and the community-driven development of the Linux operating system.
Over the years, Tux has become more than just a mascot; he is a beloved figure in the open-source world. Tux has appeared in various Linux distributions and has even starred in his own open-source games such as Tux Racer and SuperTux.
Tux has taken on a role in the Linux community similar to that which Mario holds in the Nintendo community. The character has been featured in open-source look-alikes of other mainstream games, such as Tux Kart and Tux Paint.
To learn more about Tux and his significance in the Linux community, you can visit his Wikipedia page.