Tides are caused primarily by the gravitational forces exerted by the Moon and, to a lesser extent, the Sun on Earth's oceans. The Moon's gravity pulls on Earth's water, creating bulges of water on the side of Earth closest to the Moon and also on the opposite side. These bulges correspond to high tides. As Earth rotates, different areas pass through these bulges, experiencing high tide when in a bulge and low tide when between bulges. This results in most coastal areas experiencing two high tides and two low tides approximately every 24 hours
. The Sun also influences tides, but its effect is about half that of the Moon because, despite its much larger mass, it is much farther away from Earth. When the Sun, Moon, and Earth align (during full and new moons), their combined gravitational forces create especially high and low tides called spring tides. When the Sun and Moon are at right angles relative to Earth, their gravitational forces partially cancel out, resulting in weaker neap tides
. In summary, tides are caused by the differential gravitational pull of the Moon and Sun on Earth's oceans, combined with Earth's rotation, which causes the regular rise and fall of sea levels observed as tides
