The different between violin and viola

It's not just the size (most violas are between 15 and 17 inches long). A viola player is going to read in Alto Clef and a Violinist reads in Treble Clef; viola is also occasionally written in treble clef, in the higher registers (violins never use alto clef). Also a violin and viola have different strings. They both have an A, D, and G string but the viola has a lower C string and the violin has a high E string. The sound of the strings will also sound deeper since the viola is bigger and has a lower register than the violin.

The viola bow is slightly shorter and heavier than a full-sized violin bow and a bit sturdier. Playing the instruments is quite different as it takes a good deal more bow pressure and a more dramatic (or aggressive) technique for the viola, in order to get enough sound. Many violists begin as violinists. It is difficult for children to handle a viola and most students cannot manage a full-sized viola until their teen years. And finally, the bigger the viola the more resonance; this is an eternal struggle. How large can the instrument get and still be playable?