Choirs are interesting.  They are also known as a quire, chorale, or chorus.
Are you talking about the groups with a large amount of people singing different tones and ranges to make a song?
Yes indeed.  They may perform music from a classical music repertoire.
Oh wow.  What's your favorite classical song?
I have a few, and seeing choirs being led by conductors is an amazing scene.
My favorite classical songs have to be anything by Bach
Johann Sebastian Bach
Johann Sebastian Bach (28 July 1750) was a German composer and musician of the Baroque period. He is known for instrumental compositions such as the "Art of Fugue", the "Brandenburg Concertos", and the "Goldberg Variations", and for vocal music such as the "St Matthew Passion" and the Mass in B minor. Since the 19th-century Bach Revival he has been generally regarded as one of the greatest composers of the Western art musical canon.
The Bach
Choir
A choir (; also known as a quire, chorale or chorus) is a musical ensemble of singers. Choral music, in turn, is the music written specifically for such an ensemble to perform. Choirs may perform music from the classical music repertoire, which spans from the medieval era to the present, or popular music repertoire. Most choirs are led by a conductor, who leads the performances with arm and face gestures.
A body of singers who perform together as a group is called a choir or chorus