Accordion & Concertina

Accordion

The accordion is a portable box-shaped musical instrument sometimes referred to as a squeezebox.
The performer normally plays the melody on buttons or keys on the right-hand and the accompaniment (consisting of bass and pre-set chord buttons) on the left-hand.
The acrodian is often used in Europe, North America and South America for folk music.
Accordions are made in a large number of different configurations and types, there is not yet one standard accordion.
As such, what may be technically possible to do with one accordion could be impossible with another:
The size and weight of an accordion varies depending on its type, layout and playing range, which can be as small as to have only two rows of basses and a single octave on the right-hand manual, for children, to the standard 120 bass accordion and through to large and heavy 160 bass button free-bass converter models.

Concertina

A concertina is a free-reed musical instrument, similar to various accordions and the harmonica.
It has a bellows and buttons typically on both ends of it. Each button produces one note, while accordions typically can produce chords with a single button.
Currently there are at least eleven makers of traditional hand-made concertinas, in Europe, South Africa, Australia and North America.
English concertinas were most popular as parlour instruments for classical music, while the German concertinas were more associated with the popular dance music of the day.