Standard clarinet, Contrabass and contra-alto clarinets
The Clarinet is a flute-like flared pipe, like a shawm. It is a pipe with holes, but as it is a relatively new instrument, the holes are stopped with valves rather than the fingers, while it also has a reed as resonator.
The Clarinet was invented probably by Johann Christoph Denner in the early 1700s by making improvements to the Medieval shawm. The instrument was originally called shawm, but eventually changed to clarinet, derived from the Italian clarinetto, meaning high-pitched trumpet. Many different variations of clarinets are found, and used in many different cultures under different names.
Standard clarinet, Contrabass and contra-alto clarinets
Source:
http://en.wikipedia.org/wiki/File:Clarinet.png
http://en.wikipedia.org/Clarinet.htm
The Clarinet has a single cane reed (natural, or synthetic), and the body can be made of a very wide range of materials - from different types of woods, to metals, plastic, and even rubber.
Its tone depends on many variables, ranging from the musician's technique, the range, the instrument body, the mouthpiece, and the reed properties.
Abstractly, it is a large flute with valves and a reed, as well as flare and bell.
http://www.soundsnap.com/search/audio/clarinet/score
http://www.beginband.com/sndclips.shtml