D&D Basic Monsters: Gargoyle

In D&D the gargoyle appeared as early as the original book, probably due to their close relation to medieval imagery and architecture. From the beginning gargoyles were immune to damage from non-magic weapons, a trait they've retained  throughout all editions of the game (with the exception of 4th edition), even though the rules for immunity/resistance to non-magical weapons have changed significantly though the editions.

In real life, a gargoyle is a specific stone decoration, usually in the form of some fantastic creature, used in Gothic architecture to lead water away from roofs - medieval gutters in other words. The name (from French and Latin) is possibly a reference to the gargling (or gurgling) sound it makes as water flows through them. Any figure on a building not used to convey water is known as a grotesque, and since the D&D Gargoyle has no powers relating to spewing water, they should technically be called Grotesques.