The area between the land and the sea is called the coast and because of the constant movement of the water, the shape of the coast can change over time because of erosion.
In the area of the coast you will find different features like beaches and cliffs and sand dunes and at some places also a harbor. People like to build resorts next to the sea where you can go on holiday and have some fun in the sun and sea.
The water of the sea does not only cause erosion, but it will also transports the broken pieces of shells and rocks up and down the coast where it will the 'deposit' (put it down) on the beach.
Depending on the type of rocks that are by the sea, they will form different land forms because of erosion. Some rocks like limestone, will for cliffs and others that are soft will erode and form bays.
You have now learned what impact the waves can have on the coast, but did you know there are different types of waves?
If you watch the sea you will see that the wave breaks and the water goes onto the beach - I am sure that if you have ever been on the beach you would have played and run away from this water coming onto the beach. This is called the 'swash'.
If the water the runs back into the sea, it is called the 'backwash'.
If the force of the water that comes out on the beach is stronger than the water that runs back, we call is a 'constructive' wave.
If it is the other way round it is called a 'destructive' wave.
The wave height of the constructive wave will be lower than that of the destructive wave and the constructive wave will cause a wide and flat area on the beach, where the destructive wave will cause steep areas.
