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.
Music technology (mechanical) the Byzantine Empire was the first recorded European bowed string instrument. The Persian geographer Ibn Khurradadhbih of the 9th century (d. 911) cited the Byzantine lyra as a bowed instrument equivalent to the Arab rabāb and typical instrument of the Byzantines along with the "urghun" (organ), "shilyani" (probably a type of harp or lyre) and the "salandj" (probably a bagpipe). The hurdy-gurdy was a mechanical violin using a rosined wooden wheel attached to a crank to "bow" its strings. Instruments without sound boxes like the jaw harp were also popular in the time. Early versions of the organ, fiddle (or