When you dig a hole in the ground, put an object in the hole, and cover it up with dirt, you bury it. Your dog might prefer spending the majority of his time digging holes to bury his toy collection.
You can bury something to hide it, or it can be part of a funeral ritual to bury a person who's died. You could also predict that the coming snow will bury the city, or you might bury your face in your hands if you were feeling dejected. The root of bury is the Proto-Indo-European word bhergh, "to protect or preserve." If you bury your money in the yard, maybe you're trying to protect it from thieves.