Hatteras Island is a barrier island located off the North Carolina coast. Dividing the Atlantic Ocean and the Pamlico Sound, it runs parallel to the coast, forming a bend at Cape Hatteras. It is part of North Carolina's Outer Banks and includes the communities of Rodanthe, Waves, Salvo, Avon, Buxton, Frisco, and Hatteras. It contains the largest part of the Cape Hatteras National Seashore. Prior to European settlement the island was inhabited by Croatoan Native Americans.

Barrier islands are a coastal landform, a type of dune system and sand island, where an area of sand has been formed by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few islands to more than a dozen. They are subject to change during storms and other action, but absorb energy and protect the coastlines and create areas of protected waters where wetlands may flourish. A barrier chain may extend for hundreds of kilometers, with islands periodically separated by tidal inlets. The largest barrier island in the world is Padre Island of Texas, United States, at 113 miles (182 km) long. Sometimes an important inlet may close permanently, transforming an island into a peninsula, thus creating a barrier peninsula, often including a beach, barrier beach. Though many are long and narrow, the length and width of barriers and overall morphology of barrier coasts are related to parameters including tidal range, wave energy, sediment supply, sea-level trends, and basement controls. The amount of vegetation on the barrier has a large impact on the height and evolution of the island.