Okay kiddo, so you know those big, old rocks you've seen in the pictures where people go to take pictures and stuff? Yup, that's Stonehenge! It's a very special and famous place in England where people go to learn about what our ancestors used to do a very long time ago.
Now, some people thought that it would be really cool to make their own Stonehenge! So they made miniature versions, which are called replicas. That's like making a small Lego version of your house, but with stones instead of bricks.
And guess what? Some people didn't want to make exact replicas, but they still wanted to make something inspired by Stonehenge. So they made something that looks a bit like Stonehenge, but it's different, and that's called a derivative. It's like making a new cake recipe, but using some of the same ingredients from the old recipe.
So, there are lots of replicas and derivatives of Stonehenge all around the world! Some people built them to be tourist attractions, and others built them just for fun. But all of them are special and unique in their own way, just like you are!