Tide

Tide explained in an easy to understand way:

Imagine you're trying to keep a consistent level of coffee in your cup while walking on a moving train. Just like the train's motion causes your coffee to slosh back and forth, the gravitational pull from the moon and the sun causes the ocean's water level to rise and fall. In this analogy, your coffee cup is the Earth's oceans, and the train's movement is the gravitational forces, both leading to a cyclical rise and fall in levels, whether it's coffee or ocean water.