These include marine and sub-aerial processes:
Marine processes operate upon a coastline and are connected to the sea, such as waves, tides and longshore drift.
Sub-aerial processes include processes that slowly break down the coastline, weaken the underlying rocks and allow sudden movements or erosion to happen more easily. Material is broken down in situ, remaining in or near its original position. They may affect the shape of the coastline, and include weathering, mass movement and run-off.