Gatherer is an addon for herbalists, miners and treasure hunters in World of Warcraft. It’s main purpose is to track the closest plants, deposits and treasure locations on your minimap.
The addon does not track like a tracking ability does, rather it “remembers” where you have found various items in the past. It does this whenever you gather (perform herbalism, mining or opening) on an item, and records the specific map location in its history. From then on, whenever the item comes into range of being one of the closest 1-25 (configurable) items to your present location, it will pop up on you minimap.
When you view your World Map, you will also see the item locations marked on the particular map you are viewing there.