Metals are materials made of elements on the left hand side of the periodic tables 'stair step' border starting on the left of Boron and going down and right and finishing at polonium. These elements can be mixed and combined with other elements (metals or non-metals) to create materials called alloys. Alloys are just a mix of elements and materials to create a new material with favorable properties.
Metals can be generally identified by a set of few physical properties (these a very general and there are plenty of exceptions). The main definition of a metal is an element that readily loses electrons and forms positive ions. The general bulk properties that are used to simply identify metals is that they tend to be lustrous (shiny when not oxidised), they are malleable (so can be beaten into a shape and not break), they are ductile (they can be drawn out into a wire) and that they conduct electricity; this rises from the fact that they readily lose electrons so there is a free electron 'gas' where the electrons can move around and this means that a charge can flow when an electric field is placed across the metal.
The metal that has changed the way the whole world functions and takes up a huge majority of the industry even now after over a century of its discovery and use (in terms of its modern production and composition). This metal is steel and is an alloy of mainly iron (Fe) and carbon (C) with many other constituent elements added depending on the type of steel wanted and the properties required.
Steel can be produced in a number of ways. Traditional methods utilise integrated steel processes which use energy intensive blast furnaces (to produce iron) sand basic oxygen steelmaking (to convert iron to steel). More modern methods use electric arc furnaces in which scrap steel is melted using electric currents and then formed into slabs or ingots for further processing. When the steel slab or ingot has cooled, a variety of forming operations such as rolling or extrusion are used to form the metal into flat sheet for use in cars, fridges, filing cabinets or radiators, or into beams, and heavy plate for use in construction and ship building