Tides on the [[Earth]] result from the [[Moon]]'s gravity, which is just enough stronger on the near side of the earth to attract ocean water more than on the far side. Fishermen, sailors and other observers have long noted that the twice-daily cycle of high tides and low tides is corresponds to the moon's orbit.
A noteworthy observation is that the moon is less effective at creating a tidal effect on smaller bodies of water, such as lakes. This is remains today an unexplained phenomenon.
==See also==
*[[tidal coupling]]
*[[gravitational locking]]