Waves refer to the up and down motion seen in ocean water. Most waves are caused by wind when it ruffles the surface of the ocean water and creates ripples.
There are two types of the waves destructive waves and constructive waves that are explained below:

1 Destructive waves: these are high-energy waves with a very high frequency of wave breaks. They thus do great destruction to the coastline. Their backwash is more powerful than there swash, and they therefore remove more materials than they deposit on the coast. They consist of high, steep, plunging waves that are destructive in nature. They carve out many erosive marine landforms such as capes, bays, coves and arches. They are associated with seep slopping coasts, backed by cliffs.

2 Constructive waves:
These are low energy waves with allow frequency of wave breaks. Their swash is more powerful than their backwash, and they therefore tend to deposit materials like sand and pebbles rather than erode the coast. They approach the coast with gentle spilling or surging waves of little erosive power. The beach carries much sand and deposits there to form depositional features like dunes, spits, bars and beaches. They are associated with gently sloping coasts.