Rust is primarily caused by the chemical reaction of iron with oxygen and moisture, resulting in iron oxide. This process is known as oxidation and occurs when iron or its alloys are exposed to atmospheric moisture or water. When iron reacts with oxygen in the presence of water, it forms hydrated iron(III) oxide, commonly known as rust. This phenomenon is not only a concern for preserving metal objects, but it also significantly impacts structures, vehicles, and infrastructure. Preventative measures, such as using coatings, galvanization, or stainless steel, can help reduce rust formation and prolong the lifespan of iron-based materials.