Planet Earth rotates around its axis. It takes 24 hours for the Earth to complete one of these rotations. This amount of time is called a day. 

As the Earth rotates, different sides of the planet receive sunlight. The side of the planet that faces the Sun experiences daytime, whereas the side of the planet that faces away from the Sun experiences nighttime.

As our planet rotates from the west to the east, the Sun is said to rise from the east and set in the west. 

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