* Stars shine all the time: Stars are massive balls of hot gas that produce their own light through nuclear fusion. They shine constantly, day and night.
* The Sun is a star: Our Sun is also a star, but it's so much closer to us than other stars that its light completely overwhelms the light from distant stars during the day.
* Earth's rotation and the Sun's light: The reason we see stars at night is because the Earth rotates. As the Earth spins, different parts of the planet face the Sun. When your part of the Earth is facing the Sun, it's daytime, and the Sun's light makes it impossible to see the fainter stars. When your part of the Earth is facing away from the Sun, it's nighttime, and you can see the stars.
Think of it like this: Imagine you're in a very dark room with a flashlight. The flashlight is like the Sun, and the other objects in the room are like the stars. If you shine the flashlight directly on a wall, you won't be able to see the other objects because the flashlight is too bright. But if you turn off the flashlight, you'll be able to see the other objects in the room.
