Linux is a Unix like operating system developed by Linus Torvalds.
Torvalds was inspired by Minix with a desire to add to it's functionality.
Linux is an open-source operating system, meaning that the source code is
freely available and can be altered and redistributed.
Suggestions and contributions are welcomed and considered upon submission.
Many groups contribute to Linux and release independent versions.
These independent releases are called distributions.
Some examples of Linux distributions are Fedora, Debian, Centos and Slackware.
The Linux mascot is a penguin, often called Tux, seen below.

Linus Torvalds