The term open source was supposed to remove confusion, and was deliberately chosen to emphasize what the software is, rather than what it isn't. The good news is that when the term open source was coined, just 10 years ago, the world was ready to listen, and incorporated this term into its vocabulary. The bad news is that the open source world is now so diverse, with so many licenses and commercial interests involved, that it is often hard to know whether a program is truly available on an open source basis without reading the fine print.