So, you know how movies are made, right? People act and cameras film them, and then everything gets edited together to make a movie. But sometimes, the people who make movies want things to look a certain way that they can't film in real life. That's where the schüfftan process comes in.
Basically, the schüfftan process is a way to create special effects in movies by using mirrors. Imagine you have a really big mirror, and you set it up in just the right place so that when you film someone standing in front of it, their reflection in the mirror looks like it belongs in a different place. For example, you could film someone standing in front of the mirror, and in the reflection, it looks like they're standing on top of a tall building.
This is called the schüfftan process because a guy named Eugen Schüfftan came up with the idea back in the early days of movies. He figured out how to use a semi-transparent mirror called a "Schüfftan mirror" to create all sorts of cool special effects. Using the mirror, he could make it look like actors were interacting with things that weren't really there, like giant monsters or flying cars.
Nowadays, filmmakers use all sorts of fancy computer effects to do the same things that the schüfftan process used to do with mirrors. But it's still really cool to think about how they used to make movies back in the olden days, isn't it?