The answer of your question is given below:
The rise and fall of the ocean water are known as tides
which occurred two times a day. There are the levels of the ocean so when water
covers most part of the shore that means it is on the highest level. On the
other hand, when the water retreats the shore, it is known as the low tide.
The tides are caused because of the gravity of the moon and
sun, whereas currents are caused due to heating and cooling of ocean water.