Violins. - There are many more violins than anything else in an orchestra. The violins make the core sound of an orchestra and carry the melody most of the time. They are usually divided into two parts, the first violins and the second violins.
The violin is considered a real triumph in the art of instrument making. It has enormous expressive ability and flexibility, almost as much as the human voice; it makes a lot of sound relative to its size and to the amount of effort required to play it; and it can play brilliant and intricate fast figures. Ever since the violin really came into its own, in the late 1600s, composers have loved to write solo pieces for it.
Early violins were considered dance instruments; that is, they were played in ensembles to accompany dancers. The viol da gamba, which looked a lot like the modern cello, was considered more elegant and was used more as a court and concert instrument.
In the 1500s, violins began to look somewhat the way they do today. They had four strings, instead of three like the rebec (a violin predecessor), and they were beginning to have the in-curved body and the scroll at the top like the modern violin.
Violin builders in northern Italy, especially Cremona, Milan, and Venice, were the ones to bring the violin to its highest point of advancement - a point unsurpassed even today, when top players and collectors vie for surviving Cremona violins by builders like Amati, Stradivari, and the Guarneri family - all of whom lived in northern Italy in the Baroque era.
The main change to the violin in the last two centuries has been the introduction of steel and steel-wrapped strings. Old violins used gut strings, which were harder to deal with, broke more easily, and were more difficult to tune properly. Also steel-wound strings make a more powerful sound. Other than this, though violin builders know better than to interfere with perfection!