Lapping film is a special type of material that is used to make things very smooth and shiny. It's kind of like paper, but it's made out of plastic.
Imagine you have a piece of wood that has bumps and rough spots on it. If you rub the wood with lapping film, it will slowly start to smooth out those rough spots. It's kind of like sandpaper, but much smoother and gentler.
The lapping film comes in different levels of smoothness, kind of like the different colors of belts in karate. The less smooth lapping film is like a white belt, and the smoothest lapping film is like a black belt.
People use lapping film for many different things, like smoothing out metal parts or making jewelry shiny. It takes a lot of patience and practice to use it correctly, but it can make things look really nice and polished in the end!