First, the raw materials -- either iron ore or scrap iron, depending on the process -- are converted into molten steel. The ore-based process uses a blast furnace and the scrap-based process uses an electric arc furnace.
Next, the molten steel is poured and solidified in a continuous caster.
This produces what are known as semi-finished products. These can be either slabs, which have a rectangular cross-section, or blooms or billets, which have a square cross-section. They are the blanks which are used to form the finished product.
Lastly, these semi-finished products are transformed, or "rolled" into finished products. Some of these undergo a heat treatment, known as "hot rolling". More than half the hot-rolled sheet is subsequently rolled again at ambient temperatures (known as "cold rolling"). It can then be coated with an anti-corrosion protective material.

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