Geocaching

I came to know about this thing called "Geocaching". What is it? Even I don't know but when browsing through various links, I came across the following site which offers quite a lot of information and details about Geocaching:

http://www.geocaching.com

To me it seems to be an interesting thing, but only if you are an active GPS user and you "own" a GPS device. I don't know much(didn't have time to go through all the written stuff on the site to learn more about it), so I might be wrong.

Will Explore when Time Permits