The cello is a four-string bass musical instrument of the violin group. It's a close relative of the violin, viola, and double bass.
The first cellos were constructed during the 16th century and usually designed with five strings. Cellos served to enhance the bass side in ensembles. Haydn, Mozart, and later serious composers gave aggrandized prominence to the cello in instrumental music.
Famed works for the cello include J.S. Bach’s six suites for unaccompanied cello; Beethoven’s five sonatas for cello and piano; the concertos of Antonín Dvořák, Edward Elgar, and Samuel Barber.