First, there was Foo Camp.
"Foo" is an acronymn for "Friends of O'Reilly", referring to Tim O'Reilly, founder of O'Reilly Media, a publisher of computer and technology related books.
His original "unconference" was invitation only, and was called "camp", because people actually camped out overnight. Tim still runs Foo Camps about once a year.


Then, there was BarCamp!
The spin-off is a play on the word "Foobar", a term used for placeholder elements found in incomplete software projects. (The word Foobar has its own rich etymology you can look into, though it might not be safe for work.)

BarCamp is an "unconference" where anyone can join and give presentations! (It's not "invitation only" like Foo Camp.) And, they have taken place all over the world. Most of them focusing on technology. But, a some of them have specialized in other areas, including military technology and real estate.
It has nothing much to do with bars. Though, sometimes they meet in them. It is relatively rare for people to actually camp out during  BarCamps.


Now, there is SkeptiCamp!
SkeptiCamp is very much like BarCamp, but it focuses on science and skepticism. As the popularity of science and critical thinking skills emerge, more such "camps" are bound to pop up across the world.
New York City is scheduled to have its first SkeptiCamp on December 6th, 2009.

It is common for regional BarCamps and SkeptiCamps to develop their own logo. But, the story doesn't end there!


Soon, there will be Skepchicamp!
In March 2010, Skepchick is sponsoring its version of SkeptiCamp, aimed at bringing more women involved in the realm of science and skepticism.

If we extrapolate this trend, we should be able to join "OpenskepchibarfooCamp", in 2013.