Weatherstripping is a general term for a few different types of weather seals, typically used to seal the driver's compartment off from the outside air and elements.
Weather stripping commonly consists of a soft hollow foam and an attachment section. Sometimes the attachment is a flat surface for adhesive, while others are a clamp design that attaches to a strip of metal, often pinch-welded around the opening the manufacturer intends to seal. The attachment point on the weatherstripping itself can be found at different angles.
The most common weather strip material a car owner encounters is around the driver's door. The other doors will have it as well, along with the trunk interior and even under some hoods.