Final answer:
A drip edge is a bent aluminium or galvanized metal strip that fits the edge of the entire roof to divert water runoff. It is an important component in roofing systems as it helps prevent water damage to the underlying structure of the roof.
Step-by-step explanation:
A bent aluminium or galvanized metal strip that fits the edge of the entire roof to divert water runoff is called a drip edge. It is an important component in roofing systems as it helps prevent water from seeping into the underlying structure of the roof and protects the fascia and soffit from water damage.