With the chemical formula HNO3 and also known as "strong water", Nitric Acid is a somewhat viscous liquid with no colour or smell. Old samples can become yellowish, when decomposed in nitrogen oxide and water. Given its low boiling point (83º), Nitric Acid releases characteristic "smokes", at higher concentrations.
Nowadays, industrial production of Nitric Acid is made using the Ostwald Process, a process that was actually invented by the French chemist Kuhlmann, in which Ammonia was oxidised in the presence of a catalyst. However, the first alchemists were already familiar with the substance, and produced it. In the 17th century, Johann Rudolf Glauber established the first industrial production method, by heating sulphuric acid with potassium nitrate.
Nitric Acid is used for large scale production of many chemical products, including oil specialities, and it's used to make ammonia nitrates and potassium nitrates, fertiliser and explosives bases. It is also used to oxidise metals and to manufacture colourings and artificial fibres, such as nylon or terylene.