The common name for the substance that causes rust is iron oxide. Rust forms when iron, in the presence of oxygen and moisture—usually from water—undergoes a chemical reaction called oxidation. This process leads to the deterioration of the metal, creating a reddish-brown coating on the surface. Rust can have damaging effects on structures and machinery, diminishing their strength and integrity. Preventive measures such as applying protective coatings, galvanization, or using stainless steel can help mitigate rust formation. Understanding rust, its causes, and prevention is essential in engineering and maintenance fields to prolong the lifespan of iron-containing materials.