A truffle is a fungal fruiting body that develops underground and relies on mycophagy for spore dispersal. Almost all truffles are ectomycorrhizal and are therefore usually found in close association with trees.
There are hundreds of species of truffles, but the fruiting body of some (mostly in the genus Tuber) are highly prized as a food.
The 18th-century French gastronome Brillat-Savarin called these truffles "the diamond of the kitchen". Edible truffles are held in high esteem in French, Spanish, northern Italian and Croatian cooking, as well as in international haute cuisine.
I actually had no idea there was so much to a truffle. lol