ELI5: Explain Like I'm 5

3D optical data storage

So imagine you have a book with pages that are really, really thin. These pages are so thin that you can see through them like a clear piece of plastic. Now imagine you have a special pen that can draw really tiny pictures and words on each of these thin pages.

But instead of drawing on just one side of the page, the pen can also draw on the other side and even in the middle of the page! That's kind of like how 3D optical data storage works.

Instead of pages, the 3D storage uses a very thin plastic layer that's transparent like the page. Instead of a pen, there's a special device that uses a laser beam to make tiny changes in the plastic by melting it just a little bit. This forms tiny dots that can represent digital information.

And just like the pen can draw on multiple sides of the page, the laser can make dots at different depths inside the plastic layer. This creates a 3D pattern of dots that holds information like pictures or music.

When you want to read the information, a special laser scans the plastic layer in different layers, like using a magnifying glass to see different parts of a drawing. The laser beam detects the changes in the melted dots and translates them back into digital information that can be played or viewed on a computer.