How do erosional processes along the coastline work?

There are four different ways the coastline can be eroded: Firstly, HYDRAULIC ACTION is very simply the sheer power of the water eroding the cliff face and beach. Any weaknesses, such as cracks and crevices, will make the cliff more susceptible to erosion. Abrasion is another process. It's helpful to think of sandpaper for this one (sandpaper is often described as 'abrasive'). This occurs when the material carried by the sea, such as stones and gravel, are hurled against the cliff and beach by the waves, and scour out the beach and cliff face. Abrasion is often confused with attrition, but they are very different! In attrition, the rocks don't erode the cliff or beach, but each other. Movement of the sea makes them crash together, knocking the rough edges of them. This is why you can tell how long a rock has been in the sea for, by looking at how smooth it is. Have you heard of the Scale of Roundness? This is a way of comparing the erosional power of water (often at different points along a river), by looking at the relative smoothness of the rocks present at each site. This is due to attrition. Lastly comes corrosion (or corrosion). I find corrosion easier to remember, because it reminds me of the effects of acid. That is basically what is happening- minerals and other substances dissolved in the seawater dissolve the rocks of the beach and cliff. These are how the coastline is ERODED, as the material is carried AWAY from the beach/cliff. WEATHERING processes are different, as the material remains IN THE SAME PLACE.