Jordan Smith is a builder and welding engineer who is passionate about architectural steel. In this video, he reviews the two basic types: hot-rolled and cold-rolled. Each has its advantages and disadvantages depending on where and how it is used. Smith discusses how hot-rolled steel is cheaper but less dimensionally accurate. It also has a characteristic "mill scale" surface which can be challenging to paint. Cold-rolled steel is more expensive but stronger, harder, dimensionally precise, and features a smooth, bright steely finish. In the second half of the video, Smith puts on his engineering hat to explain the elastic vs. plastic deformation properties of steel and Young's modulus (the ratio of tensile stress to strain).