Steel grades refer to the classification of steel based on its chemical composition and physical properties. These grades help identify the specific characteristics of the steel, such as strength, ductility, and corrosion resistance. Common systems for categorizing steel grades include the American Iron and Steel Institute (AISI) and the Society of Automotive Engineers (SAE) standards. Different steel grades are used for various applications, from construction to manufacturing. For example, stainless steel grades are known for their resistance to rust, making them ideal for kitchen appliances, while carbon steel grades are often used in structural applications due to their strength and durability.