AoE stands for Area of Effect. This term is used to describe certain heroes and certain spells. A spell is considered AoE if its effect occurs in a defined radius. Some examples of AoE spells are Blizzard, Flame Strike, and Sheepfall. A hero is considered an AoE hero if the majority of his spells are AoE spells or if the hero's main spell is an AoE. Other types of spells include channeling, aura, single target, and DoT.