Define Alloy. Give an example for an Alloy and it's use.

An alloy is a homogeneous mixture of two or more elements. With at least one of the elements being a metal. Alloys are created to impart desirable properties such as hardness and corrosion resistance to a base metal.
Brass is an alloy of copper and zinc and bronze is an alloy of copper and tin. Some other common alloys are carbon steel, stainless steel, white gold, sterling silver and pewter.
An alloy is not a compound because it doesn't have a fixed ratio of elements. Its composition can vary. 
An example of an alloy having properties not found in its constituent metals is the bronze bell. Bronze has been used to cast bells and cymbals since ancient times because of its acoustic clarity and resonance. A bronze bell, when struck, produces a lengthy tone.
Alloys are produced by heating metals to a temperature than mobilizes the atoms so that they mix. Molten mixtures of metals can then be cast into shapes or cooled and milled. 
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