Stars are enormous balls of fire that burn from a nuclear reaction at their core. They are so bright that their light travels very far and so we can see them hanging in our dark night sky from millions of miles away.
Because they are very, very large and extremely powerful. The sun is not actually a large star – it is just that it is our closest star, and this is why it can light everything up and appear so big and bright. During the daytime, we can’t make out the stars because the light from the sun drowns them out. But the Earth rotates on its axis every 24 hours to give us a cycle of day (we are facing the sun) and night (when we are facing away from the sun). In the night-time, we can see the lights from all the other stars.
We can see them because they’re very bright – even though they’re really far away. And there are so so so many that are out there that we can’t see, because they’re just too far away. And some are a bit too small – there is a whole range of sizes that stars can be, from white dwarfs up to super giants!