Steel has a number of properties, including: hardness, toughness, tensile strength, yield strength, elongation, fatigue strength, corrosion, plasticity, malleability and creep.

Iron and steel are used widely in the construction of roads, railways, other infrastructure, appliances, and buildings. Most large modern structures, such as stadiums and skyscrapers, bridges, and airports, are supported by a steel skeleton. Even those with a concrete structure employ steel for reinforcing.

The physical properties of steel include: high strength, low weight, durability, ductility and corrosive resistance. Steel offers great strength, even though it is light in weight. In fact, the ratio of strength to weight for steel is lower than any other building material.