Steel grades refer to the classification of steel based on its chemical composition and physical properties. Different grades are designed for specific applications, ensuring that the steel meets the required strength, ductility, and corrosion resistance. Common grading systems include the American Iron and Steel Institute (AISI) and the European Standard (EN). Each steel grade is identified by a unique code or number, which indicates its alloying elements and their percentages. For example, stainless steel grades often contain chromium and nickel, enhancing their resistance to rust and oxidation. Understanding steel grades helps manufacturers select the right material for construction, automotive, and other industries.