for example, soprano. =)
Then, individual teachers can add different things like numbers and letters. For example, in my choir class this year we have all girls. We have Soprano One's (the highest voices, I'm included), Soprano Two's (a bit lower), Alto One's (even lower), and Alto Two's (the lowest)... Other things can be done like that as well :)
Oh yeah, most choirs will have just Soprano, Alto, Tenor & Bass. Most music is written for four parts. Sometimes they will break up the Sopranos and Altos to make a Soprano 2 if the piece they are singing requires that part. And the same with Tenor and Bass if they need to create a Baritone part.
There are too many to list. A few more:
basso profundo contralto countertenor castrato
Many of these can be further subdivided into lyric, dramatic, bel canto, and coloratura
Coloratura sopranos with their vocal acrobatics are my favorite.
I sing in one that only has a soprano part and an alto part, but then again there are other parts like the bass ones and tenor. But they are not that common.
Soprano Mezzo-Soprano Alto Tenor Baritone Bass
Sometimes Soprano and Mezzo-Soprano are called Soprano 1 & 2, 1 being the higher.
I believe it's Soprano, Alto, Tenor, Bass :)
Bass, Alto, Tenor, and Soprano.