eli5 why does putting toothpaste on scratched disks fix them?

Question

As the title says why does toothpaste fix disks

In: 2049

Answer 1

I think an important piece of knowledge, if you didn’t know it, is the the information on a disk is located *inside* the plastic surface. The plastic serves to protect that surface and make the disc rigid, but it’s not like a record where the outermost surface has the important information on it.

So the rubbing with tooth paste polishes down the scratch the screwed up the laser’s ability to travel through the plastic and read the information hidden inside. It’s not like it’s abrading away the information itself.