The word concertina generally refers to the bellows but these little squeeze boxes can pack a real punch in a session. There are many different versions of this instrument, some play the same note for blow and suck, others play different notes and there are a wide variety of tuning systems adapted for a range of uses. The most common version used in Celtic music as a melody instrument is the “Anglo-Concertina” with “Jeffries” tuning configuration. Definitely do your research before buying anything if the concertina has piqued your interest.
Who you should listen to: Noel Hill, Cormac Begley