Open source is primarily about software licensing.
Open source is about giving software away for free and allowing others to redistribute it.
These are important factors, but more importantly, OSS is about collaboration . Linux is a tremendous achievement, but the Internet and the WWW are the greatest OSS success stories to date. Less often considered is the role of Usenet in mothering the Net we now know. Usenet, that vast distributed bulletin board. This was a true collaborative network, where mail and news were relayed from one cooperating site to another, often taking days to travel from one end of the net to another.