An eave is the area of a roof that hangs beyond the exterior wall. The rake of a roof is the outer edge that runs from the eave to the ridge, or peak, of the roof. It is typically perpendicular to the eave.
The purpose of the eave is to keep rainwater away from the walls of the house. Eaves also protect pathways around the house by preventing washout around the footers and base. In modern houses, there are eave screens underneath each eave. These screens allow fresh air to pass through the attic, helping to keep the attic from overheating.