There are three main processes at work in the sea. These are erosion, transportation and deposition.
Erosion is the wearing away of the land by the sea. This often involves destructive waves wearing away the coast. There are five main processes which cause coastal erosion. These are corrasion, abrasion, hydraulic action, attrition and corrosion/solution.
What are the processes of coastal erosion?
Corrasion is when waves pick up beach material (e.g. pebbles) and hurl them at the base of a cliff.
Abrasion occurs as breaking waves which contain sand and larger fragments erode the shoreline or headland. It is commonly known as the sand paper effect.
When waves hit the base of a cliff air is compressed into cracks. When the wave retreats the air rushes out of the gap. Often this causes cliff material to break away. This process is known as hydraulic action.
Attrition is when waves cause rocks and pebbles to bump into each other and break up.
Corrosion/solution is when certain types of cliff erode as a result of weak acids in the sea.
You can view animations of each of these processes here (this will open in a new window/tab).
You can find out about the landforms created as the result of coastal erosion here.
Find out about coastal transportation
Find out about coastal depostion