Want is Barbershop?
Barbershop harmony is a style of unaccompanied vocal music characterized by four-part chords for every melody note in a predominantly homophonic texture.  The melody is consistently sung by the lead, with the tenor harmonizing above the melody, the bass singing the lowest harmonizing notes, and the baritone completing the chord.
The Four Parts:  

TENOR is a harmony part sung consistently above the lead. Although tenor is the highest voice in barbershop harmony, it should not be confused with soprano of conventional choral singing. The  tenor should have a light,sweet, pure tone that will compliment but not overpower the lead voice.
LEAD is the melody and is sung in the range between A below middle C, and C above middle C.

BARITONE covers approximately the same range as lead. The baritone harmony notes cross the lead notes, sometimes sung below and sometimes above. Baritones must constantly adjust their balance to accommodate their position in the chord.

BASS singers should have a rich, mellow voice and be able to sing the E flat below middle C easily. Basses should not be confused with the alto of conventional groups. Many altos can sing the bass part, but others are better suited to lead or baritone.