What does "smite" do in Minecraft?

In "Minecraft," "Smite" is an enchantment that players apply to weapons at an enchantment table, at an anvil or with the help of a villager. "Smite" is applied to axes or swords, and gives the item extra damage against undead mobs.

When "Smite" is added to a weapon, it grants bonus damage against any mob that is undead, including skeletons, zombies, withers, wither skeletons and zombie pigmen. Each level of "Smite" adds an extra 2.5 damage to each hit to one of these mobs. The maximum level is "Smite V," which is the fifth level. A player cannot apply "Smite" to a weapon that already has "Sharpness" or "Bane of Arthropods" applied to it, because these enchantments are mutually exclusive.