The clarinet is a woodwind instrument in the single reed family. Generally clarinets have been called a woodwind instrument because they were historically made of wood. For several decades now, the clarinet has been available in a plastic or resonite composite form. This has made them more affordable and less effected by temperature.

Clarinets have many shapes, sizes, and range, or keys. The most popular is the soprano clarinet which plays in the key of B-flat. This is the clarinet that's seen in orchestras, dixie bands, concert bands, etc. The other clarinets made are named with regards to their note range, that is how low or how high they play and sound. Other clarinets include the sopranino E-flat clarinet, the E-flat Alto clarinet, the A-clarinet,the B-flat Bass clarinet, and the Contrabass clarinet which is pitched at either E-flat or B-flat.
The clarinet is descended from the European 'chalumeau' which was developed in the late 17th century. Over the years, physical keys were gradually added to the instrument and the clarinet has enjoyed it's current design for the last 40 years.