Accordion is a musical instrument that is played by pulling and pushing in and out its bellows while pressing keys that produce different notes. Some of the synonyms for accordion are concertina, bandoneon, harmonica, melodeon, and squeezebox. Concertinas are smaller and have hexagonal ends, while squeezing them in and out produces varying pitch and tone. Bandoneon is typically used in Tango music and is known for its harsh sound. Harmonicas, or mouth organs, are small and portable and are played by blowing air through them. Melodeons are button accordions, while squeezebox is another word commonly used to describe the accordion. All these musical instruments produce unique and melodious sound perfect for a variety of musical genres.