Cashew trees yield what is commonly referred to as a drupe, a fruit with a thin flesh and a large single seed much like a peach. The cashew apple (as it's called) differs from the peach in that its seed "falls" to the bud end of the fruit insead of staying in the center.
Cashew apples can be eaten as well, and the nature of their seed residing on one end means that they're also easily prepped, but the fruit quickly take on a mealy texture and bitter taste once harvested. If eaten soon after harvest, the fruit posses a very sweet flavor similar to that of
reticulated rind melons such as cantaloupe and honeydew. Eating the fruit itself is the minor usage of the product of the cashew tree.
Cashew nuts aren't sold in the shell because the oil they contain and release as they break down is harmful (it has caustic properties) if consumed and has the ability to eat away at organic material as a result of prolonged contact--think (but don't drink!) drain cleaner.
The second most common usage of the cashew tree's yield is allowing the cashew apples to ferment into a spirit referred to as "feni" or "fenny", with a sweet flavor like wine made from late harvest grapes, an unusual aftertaste and an acerbic (sour/bitter) aroma.
