Waves on the ocean can be cause by many things, from the wake of ships to earthquakes.  Wind is probably the biggest generator of surface waves on the sea. Wave patterns can also be influenced by tidal currents and general ocean circulation patterns. Perhaps the most noticeable pattern of waves is near the shore, here we can see waves breaking. A tremendous amount of frictional , potential and kinetic energy is generated in the surf zone. Because of this it can be the most treacherous. 

As waves approach the shore, the sea floor creates friction on the motion of the wave which causes the crest of the wave to fall over (or break) in the direction of its travel. Hence, the types of waves that you see , and the break pattern can tell plenty about the sea floor in the surf zone.  The height of wave is determined by the depth of the sea floor below them,  and many Hollywood movies show towering waves on very shallow sea floors, a good example of Hollywood trickery.  A large wave (height)requires plenty of water depth. As a rough rule the height of a wave requires the same depth below it to keep forward motion, otherwise it begins to break.

This is important when in a vessel at sea.  It is often important to stay in deep water to avoid breaking waves. When in a vessel at sea and hit by a breaking wave in the surf zone it is often safer to head out to sea to deeper water.