Stella this side....Steel reinforcement is a steel bar or a mesh of steel wires used as a tension device in reinforced concrete and reinforced masonry buildings to strengthen and aid the solid while it is under stress. Under pressure, concrete solidifies. Its tensile strength, however, is poor. Rebar, also known as reinforcement steel or reinforcing steel, is a steel bar or mesh of steel wires used to strengthen and keep the concrete in tension in reinforced concrete and masonry constructions. The surface of rebar is frequently textured to increase the bonding quality with concrete. For further detail have a look on website.