Most places experience two high tides each day

Tides are the regular rise and fall in water level experienced by seas and oceans in response to the gravitational pull of the Moon and the Sun and the effects of the Earth's rotation. During each tidal cycle, at any given place the water rises to a maximum height known as "high tide" before ebbing away again to the minimum "low tide" level. As the water recedes, it uncovers more and more of the foreshore, also known as the intertidal zone. The difference in height between the high tide and low tide is known as the tidal range.[32]

Most places experience two high tides each day, occurring at intervals of about 12 hours and 25 minutes. This is half the 24 hours and 50 minutes that the Moon takes to make a complete rotation of the Earth and return to the same position in the sky. The Moon is 27 million times smaller than the Sun, but it is 400 times closer to the Earth. This means that its gravitational pull at the Earth's surface is more than twice as great as that of the Sun.[33] The tidal force caused by the Moon draws the sea towards it while inertial forces act to keep the water in place. The gravitational force is stronger so a bulge forms in the ocean at the place where the Earth and Moon are at their closest. On the opposite side of the globe, the lunar force is at its weakest and the inertial force is stronger than the gravitational pull and this causes another bulge to form. As the Moon rotates around the Earth, so do these ocean bulges move around the globe. The gravitational force of the Sun is also working on the seas. It is less powerful than that of the Moon, and when the Sun, Moon and Earth are all aligned (full moon and new moon), their combined gravitational pulls results in abnormally high "spring tides". When the Sun is at 90° from the Moon as viewed from Earth, it counteracts the pull of the Moon and the tidal range is smaller, causing "neap tides" to occu

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