The double bass, also known simply as the bass (or ), is the largest and lowest-pitched bowed (or plucked) string instrument in the modern symphony orchestra (excluding unorthodox additions such as the octobass). Similar in structure to the cello, it has four, although occasionally five, strings. The instrument's exact lineage is still a matter of some debate, with scholars divided on whether the bass is derived from the viol or the violin family.