Answer:
Tides are very long-period waves that move through the oceans in response to the forces exerted by the moon and sun. They originate in the oceans and progress toward the coastlines where they appear as the regular rise and fall of the sea surface. When the highest part or crest of the wave reaches a particular location, high tide occurs; low tide corresponds to the lowest part of the wave, or its trough. The difference in height between the high tide and the low tide is called the tidal range. Tidal range is the height difference between high tide and low tide.