An alloy is a mixture of metals or a mixture of metals and other nonmetal substances. Essentially, an alloy is a material that is made up of at least two separate materials, at least one of them being metal. Different substances or metals can be combined to take advantage of certain properties of the base substance. For example, pure iron is a strong substance, but is prone to rust very easily.  Creating an iron alloy might allow us to take advantage of iron’s strength while warding of rust through the use of a separate material.  Most of the “metals” we use in our daily lives are actually alloys as opposed to pure versions of the metal.