Areoles are specialized structures on the cactus stem. They are actually modified buds and can produce not only spines but also:
* Flowers: Cactus flowers arise from areoles.
* Glochids: These are tiny, barbed hairs that easily detach and can cause irritation.
* Branches: Some cacti can branch from their areoles.
So, in a way, you can think of areoles as the "multi-purpose" organs of a cactus!