1) Beaches form in sheltered environments like bays through the process of deposition when the swash is stronger than the backwash. 2) Spits are formed through the process of longshore drift, where the direction of wind and wave action causes sediment to be deposited in a curved shape extending from the coastline. 3) Tombolos and bars are both types of coastal landforms formed through longshore drift - a tombolo joins an island to the mainland, while a bar joins two headlands across a bay.