The clarinet is a musical instrument that is a part of the woodwind family. The clarinet's name is derived from the Italian word "clarino," which is a type of trumpet; then adding the suffix "-et," meaning little. The first clarinets had a tone similar to a trumpet. The instrument has a cylindrical bore and uses a single reed. Sound is produced when air is blown through the opening between the reed and the mouthpiece, and the reed vibrates. The clarinet family is used in an orchestral setting to provide color, especially with regards to harmonies. Classical and romantic composers often featured clarinet solos, relying on its unique tone and range.

The clarinet is typically made of wood, but different models are available dependent upon price and the skill of the player, or clarinetist. They have been made from many different materials since their invention such as plastic, metal, resin, hard rubber, and even ivory. Most professional clarinetists use instruments made of African hardwood, grenadilla, or Honduran rosewood, although no new instruments are being manufactured from the latter, as supplies are rapidly diminishing. Historically, boxwood and cocobolo have been used as well. Most students use an inexpensive instrument made of a plastic resin, trademarked by Selmer, a manufacturer of mostly student and intermediate model instruments, as "resonite." 

Mouthpieces are generally made of hard rubber, although some inexpensive mouthpieces may be made of plastic. However, other materials such as crystal, glass, wood, ivory, and metal have been used. The ligature, the device that holds the thin reed against the mouthpiece, is often made out of metal and plated in nickel, silver or gold. Other ligature materials may include wire, plastic, string, or leather. The instrument's single reed is made from the cane of Arundo donax, a type of grass. Reeds may also be manufactured from synthetic materials. 

Of all the woodwind instruments, clarinets have the largest pitch range. Although there are many types of clarinets in different sizes and pitches, the unmodified word clarinet usually refers to the B flat clarinet, which is the most popular type. The clarinet has a bright and mellow sound. It has often been said that its tone is the closest to that of the human voice. It is used in classical music, concert bands, jazz bands, marching bands, chamber music, and even as a solo instrument. Concert bands use clarinets in the same space, and they often play the same notes as the string instruments in an orchestra. Several types of clarinets may be used in a concert band to cover the variety of parts to be played. 

The modern design of the clarinet used in most of the world today was introduced by Hyacinthe Klosé in 1839.. He devised a different arrangement of keys and finger holes to allow simpler fingering. This new system was slow to gain popularity because it meant the player had to relearn how to play the instrument. To ease this transition, Klose wrote a series of exercises for the clarinet, designed to teach his fingering system. However, the new system made the instrument much easier to learn to play. Gradually it became the standard, and today the Boehm system is used everywhere in the world except Germany and Austria. 

Playing the clarinet is an exciting option for children even as young as three. A child starting this early would most like have to learn a smaller clarinet, such as the C, as it is much more ideal for small hands. The student could then progress to the more common, but also larger and heavier B flat clarinet. While lessons are available for children of any age, the public school systems in the United States often do not introduce instrumental music until the fifth grade and beyond.