A childhood belief about films

I used to believe that movies were made in the exact order shown on screen.
I used to think it would take years and years to make films that way.
I thought that one scene was filmed then everyone packed up and moved to another location or whatever to film the next scene.
It wasn't until I saw a 'behind the scenes' programme on telly showing that they filmed all their scenes at the one location and then moved on.
Then it clicked.
Sadly this wasn't till in my teens.