Violin, often referred to as the fiddle, is a great beginning instrument. Students will develop the musical ear and technique with the Suzuki series and music reading skills with the Essential Elements series.
Viola looks a lot like the violin, but has a richer, warmer, mellow sound. The viola plays the counter melody or harmony in the symphony. It fit in between the violin and cello parts. Often students begin on violin and later transition to viola.
The cello is even deeper, richer, and warmer than the viola. This is like the tenor voice of a choir. It's very large, and is played seated with it held upright with the bottom resting on the floor. They make child sized cellos for young beginnings to use.
Double Bass is the largest, lowest string instrument. This is usually played standing. Students typically begin on cello before transitioning to double bass. This instrument plays the cool walking bass part in a jazz ensemble.