A diatonic accordion is a type of free-reed musical instrument that produces sound when air flows over reeds. Unlike the chromatic accordion, it is designed to play in specific keys, typically featuring a limited number of notes. This makes it popular in folk music traditions around the world. The diatonic accordion has buttons on the right side for melody and buttons on the left for chords and bass notes. It is often used in genres like Cajun, Irish, and Polka music, where its distinctive sound adds a lively character to performances.