What Is Rust?

Rust is a thing where any amount of iron reacts with oxygen or water and then tottrades and corrodes. chromium, as an element, when it's added to steel, creates a protective film around the iron. It only takes a few atomic layers to reduce the corrosion to super low levels. And apparently, for something to be called stainless steel, it has to be at least ten % chromium,. There's even an official level that you have to reach to be the real product.