accordions

The accordion is a portable wind instrument. Sound is produced by free reeds that vibrate when air is directed across them by bellows. The player operates keys or buttons to select pitches while expanding and contracting the bellows to push air through the reeds.

A typical instrument has two main sections connected by the bellows: a treble side with a keyboard or button interface for melody, and a bass side with buttons for accompaniment. The bellows act as an air pump, controlled by the player's hands.

There are two broad families: the piano accordion, which uses a piano-style keyboard on the melody side, and the button accordion, which uses button layouts on the melody side. Within both families, chromatic and diatonic varieties distinguish their range and fingering.

The modern accordion emerged in early 19th century Europe, with contributions from German instrument maker Christian Friedrich Ludwig Buschmann and later Cyrill Demian of Vienna. It rapidly spread worldwide and became a staple of many folk and popular music traditions.

In the Americas and Europe, accordions are central to Cajun and Zydeco music, Argentine tango, Polka, and various traditional folk styles. They have also appeared in classical and contemporary genres, and electronic variants extend the instrument with digital sounds.