What Are Tides?

This website offers a easy to follow animation of the moon revolving around the Earth and how this effects whether or not one part of the Earth is experiencing a spring or neap tide. This website also gives a clear description of the different strength levels on the Earths gravitational pulls. The animation of the tidal bulge illustrates how the gravity "stretches" the water towards the moon.
http://www.mmscrusaders.com/newscirocks/tides/tideanim.htm