Re: [OT] free software vs open source was: Re: codesearch.el 1.0 --- Search for code via Google Code Search

[Richard Stallman]

    From what I've read I'd expect
    that free software is a subset of open source software (i.e. not all open
    source software is free in the sense that it protects our freedoms).

That looks like a common misunderstanding, based on confusing "free"
with "copyleft".  A license is a free software license if it respects
the four freedoms.  Copyleft licenses go further and defend the four
freedoms.  However, there are non-copyleft free software licenses,
including the original BSD license, the revised BSD license, and the
X11 license.  See http://www.gnu.org/licenses/license-list.html for
more info.

Free software and open source are the names of two philosophical
camps.  The free software camp is concerned about freedom; the open
source camp says it is not important.  By choosing the term "free software"
we direct attention towards issues of freedom.  That is very important.