Sure thing. The atomic layout of steel—how the iron atoms line up in a crystal grid and the little carbon atoms that slip in between—decides how hard it is to stretch or bend it. In the shop we don’t see atoms, we see the numbers on the steel tag: yield strength, tensile strength, that sort of thing. If a beam is stamped with a yield of 50 ksi, that means it can take that many pounds per square inch before it starts to permanently deform. So when we lift or weld, we just check the grade, make sure the load we’re pulling is under that number, and keep the welds tight so the steel stays in one piece. In short: atoms set the limits, the numbers on the plate tell us those limits, and we just follow them.