Geocaching, first coined by Matt Stum on May 30, 2000, was the joining of two familiar words. The prefix geo, for Earth, was used to describe the global nature of the activity, but also for its use in familiar topics in gps such as geography.
Caching, from the word cache, has two different meanings, which makes it very appropriate for the activity. A French word invented in 1797, the original definition referred to a hiding place someone would use to temporarily store items.
The second use of cache has more recently been used in technology. Memory cache is computer storage that is used to quickly retrieve frequently used information. Your web browser, for example, stores images on disk so you don't have to retrieve the same image every time you visit similar pages.
The combination of Earth, hiding, and technology made geocaching an excellent term for the activity.
However, “geocaching” was not the original name of this hobby. What was the original and most widely used name until September 2000.
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