As mentioned earlier, steel is an example of an interstitial alloy. The small carbon atoms fit into gaps in the iron's crystal lattice structure.
Carbon Steel: This refers specifically to steel where carbon content varies, affecting properties such as hardness and ductility.
Stainless Steel: A specific type of steel that contains chromium which forms a protective layer on its surface preventing rust. It's an example showing how adding different elements can create alloys with unique properties.