I find it hard to believe that it was 10 years ago that Eric Raymond and Bruce Perens deliberately coined the phrase "open source." To me, it seemed like only yesterday that Eric and I, who've known each other for-cough-30 years-cough-had talked about the need for a term for "free software" that didn't carry all its baggage.
At the time, "free software" had-and still does have, for that matter-two problems. The first is that, no matter how often you tell people that it's free-as in "free speech," not free as in "free beer"-many people still don't get it. That's why even now people can ask, in all sincerity, how you can make money from FOSS (free and open-source software).
The other problem is that "free software," as defined by Richard M. Stallman, aka RMS, who codified FOSS with the GPL (Gnu General Public License), carried a lot of other baggage with it besides opening up software code. Without going into the decade-long arguments between open-source and free-software advocates, the emphasis in open source is on the pragmatic use of open-source software, while free software puts the idealism of open code ahead of what some see as practical considerations.