Linux
From OpenSourceGov
Linux is a generic term referring to Unix-like computer operating systems based on the Linux kernel. Their development is one of the most prominent examples of free and open source software collaboration; typically all the underlying source code can be used, freely modified, and redistributed by anyone under the terms of the GNU GPL and other free licenses.
There is no single distribution of Linux, instead different organisations produce different flavours of the operating system. Some are free to download, others must be paid for and come with discs, manuals etc.
