Reinforced concrete is the integration of steel into concrete before the concrete has set. Typically steel bars are embedded into the concrete. This steel is commonly known as rebar but it's not the only method used to reinforce concrete; post-tensioning is an alternate method for reinforcement. This composite material is superior to either concrete or the steel and allows engineers to create a variety of shapes and structures that would not be possible otherwise. A commercial-grade concrete chainsaw can cut through this material. The steel will not rust because the alkaline nature of the concrete will prevent corrosion.