This feature is what distinguishes it from a regular sweatshirt and provides its core function:
Warmth and Protection: The hood offers extra warmth around the head and neck, and provides protection from wind, light rain, or cold weather.
Drawstrings: Many hoods include drawstrings for adjustment, allowing the wearer to tighten the hood for better coverage.
Another key feature that is strongly associated with a hoodie is the kangaroo pocket, which adds functionality for hand-warming and storage.