Linus Torvalds wrote the first version of the Linux Kernel in 1991 while still a student at the University of Helsinki. He released version 0.02 in 1991. The version 1.0 of the Linux kernel is the core of the operating system and it was released in 1994. Linus Torvalds only developed the Linux Kernel. The Linux operating system was developed by millions of developer all around the world.

Tux - Vikipedi

A penguin is the official mascot for Linux and was announced in 1996. The penguin was called TUX.