The invention of differential gear was a game changer for many industries. However, the most notable improvement was seen in automotive drivetrains. From a layman’s point of view, it looks like that a differential gear system will have a very simple operation. However, a look inside will tell you that it is a work of art. Check out this cool animation and see for yourself.
I liked the animation very much, it slaves me lots of readingtime in wanting to understand how things work. You said it well, these things had become works of art.