The clarinet is a type of woodwind instrument that has a single-reed mouthpiece, a straight cylindrical tube with an approximately cylindrical bore, and a flaring bell. A person who plays the clarinet is called a clarinetist.
There are many types of clarinets of differing sizes and pitches, comprising a large family of instruments. The unmodified word clarinet usually refers to the B♭ soprano clarinet, by far the most common type, which has a large range of nearly four octaves. The clarinet family is the largest woodwind family, with more than a dozen types, ranging from the (extremely rare) BBB♭ octo-contrabass to the A♭ piccolo clarinet. Of these, many are rare or obsolete (there is only one BBB♭ octo-contrabass clarinet in existence, for example), and music written for them is usually played on more common versions of the instrument.
Johann Christoph Denner invented the clarinet in Germany around the turn of the 18th century by adding a register key to the earlier chalumeau. Over time, additional keywork and airtight pads were added to improve tone and playability. Today, the clarinet is used in jazz and classical ensembles, in chamber groups, and as a solo instrument.