The violin originated in 16th century Italy where it was first seen in paintings by Ferrari. The violin has a body made mostly of wood and consists of two main parts: the violin and the bow. The bow is made of different materials and is the same length as the player's right arm. It helps produce sound by creating friction between the horsehair strands and the strings. The body of the violin contains many components that each play a role in producing sound, such as the bridge which transmits string vibrations, and the sound post which helps the front and back plates vibrate together. Hundreds of pieces of music have been composed for violins, including concertos for solo violin accompanied by an orchestra.