How 3D holograms work?

A 3D hologram is like a picture that you can look at from different sides and it changes, just like how your favorite toy looks different when you turn it around.

Imagine you have a flashlight and you shine it on a piece of paper with holes in it. On the wall, you see shapes, this is like shadow puppetry. Now imagine instead of one piece of paper, there are many layers of paper, each with tiny holes that match up perfectly. When you shine the light through all these layers, it creates a picture that looks 3D on the wall, like a little scene from your favorite cartoon.

Each layer is like a page in a book, if you have just one page, you only see part of the story. But when you stack many pages together and look at them all at once, it’s like reading the whole book! The hologram uses many tiny pictures, almost like a movie, to make something that looks real and can be seen from different angles.

Even though it feels special, there's no magic involved. It's just light passing through layers of tiny holes, just like how your shadow changes shape when you move around a lamp!