The double bass (also called the string bass, upright bass, bass violin or contrabass) is the largest and lowest-pitched bowed stringed instrument in the violin family and the modern symphony orchestra. It is also used in jazz ensembles frequently – especially played pizzicato. It is not as loud as many other instruments due to its low range.
Keep in mind that performing on bass can be physically demanding because the strings are large and thick. Children are unable to start playing the instrument until their hand size and height allow them to play a 3/4-size model (the most commonly available size). The bass is usually discouraged for people with shorter arms and smaller hands due to the big note gaps and the thick strings. Due to physical consideration, most players do not use the 5th (little) finger, as it is too weak to produce a reliable tone.