Enchanted arrows are arrows that have magical effects, but unlike enchanted weapons, they cannot be recharged or retrieved after firing, as they disappear. Also unlike normal weapons, they cannot be enchanted with sigil stones or at an enchanting altar.
Enchanted arrows come in all different types, Glass, Daedric, Dwarven, Elven, etc. Also, pay attention to the effects, because some have affects in a large area. Ex: Arrow of Cleansing; 40 fire damage in 10 feet for two seconds.
Enchanted arrows, like enchanted weapons, can be used on ghosts, wraiths, liches, unicorns, and other enemies unaffected by normal weapons. They are a useful tool for novice archers, because most of them deal some serious damage.