Well, little one, time travel is a bit like having a magic key that opens doors to different rooms. Each room is a different time in history. When you walk into a room, you'll be able to see everything that happened in the past and if you go to another room, you could even see things happening in the future! We use a special science called 'physics' to help us create that magic key, and with it, we can visit all the amazing moments in history or maybe even see some exciting things that haven't happened yet!
Imagine you are a world-renowned scientist who recently discovered time travel. How would you explain the science behind it to a young child?