"What is open source?
Back in 1997, Bruce Perens, a prominent Linux operating system
developer, wrote a document concerning the distribution and
development of the Debian Linux distribution. He later removed
references to Debian and created what is now known as new. Among
other things, the Definition states that open source software must
be distributed without royalty, that the distributor must make the
source code for the software freely available, and the derivative
works from the code must also be released as open source.
"Open source is essentially a cousin of the Free Software
Movement, created in 1983 by Richard Stallman to promote the free
distribution of software unfettered by standard proprietary code
restrictions. Free software's rules are codified by the General
Public License (GPL), which as of October 2006 was under review for
its third revision."