Hurdy-gurdy twenty-three different forms, and there is still no standardized design today. The six-stringed French "vielle à roue" is the best known and most common sort. A number of regional forms developed, but outside France the instrument was considered a folk instrument and there were no schools of construction that could have determined a standard form. There are two primary body styles for contemporary instruments: guitar-bodied and lute-backed. Both forms are found in French-speaking areas, while guitar-bodied instruments are the general form elsewhere. The box form of the "simphonia" is also commonly found among players of early music and historical re-enactors.
Hurdy-gurdy a common bridge, and a relatively small wheel. Due to its size, the organistrum was played by two people, one of whom turned the crank while the other pulled the keys upward. Pulling keys upward is cumbersome, so only slow tunes could be played on the organistrum. The pitches on the organistrum were set according to Pythagorean temperament and the instrument was primarily used in monastic and church settings to accompany choral music. Abbot Odo of Cluny (died 942) is supposed to have written a short description of the construction of the organistrum entitled "Quomodo organistrum construatur" (How the Organistrum