We can break the instruments into four families. Each family is grouped by the way the instrument produces vibration. This kind of classification gives us the string family, the woodwind family, the brass family and the [?] family. String instruments make up the majority of the instruments in the orchestra. All string instruments use string vibration to produce sound. There are four main string instruments, these are the [?], the viola, the cello and the bass. Each of these instruments can be plucked or bowed. A very common arrangement would have the violins playing the melody and the violas cellos and basses playing supporting roles. Lastly the [?] and the piano are included in the string family. The next largest section of the orchestra is usually the [?] family. Most woodwind instruments use a small piece of wood called a reed to produce their vibration. The reed vibrates when air is blown across it. This is how instruments like the clarinet work. Some woodwind instruments have a reed that has two parts called a double [?] instruments, like the oboe and the [?]. In this case both reeds vibrate and tend to create a nasal sound. The brass family gets its name from the shiny material that its instruments are made from. All brass instruments use the players lip vibration and air to make sound. The five main brass instruments in the orchestra are the trumpet, the horn, the trombone, the euphonium and the [?]. In the back of the orchestra we have the percussion family, known for its loud banging and crashing. The percussion family has instruments that are struck or shaken to make their vibrations. The percussion family includes cymbals, auxiliary percussion liked the tambourine, triangle, shakers or [?] and mallet instruments like bells, xylophone and marimba. Most of the time percussion instruments play a supporting role.