What are the differences in singing voices?

Well. Of course every singer has a different, unique timbre and thus a different voice, but there are also specific terms relating to voice type of course. In a choir the typical setup is SATB, or Soprano, Alto, Tenor and Bass. These can all be split up as well. Examples of different types of tenors are lyrical tenors, dramatic tenors, spinto tenors etc. etc. There are so many. You can also have countertenors, which are male singers that sing the alto part or even soprano, though this is rarer, They are effectively singing in their falsetto range. Castrati, although they no longer exist (supposedly), were men who could truly sing soprano, but were castrated prior to puberty to retain their boy soprano voices (or had medical issues in some cases). Basses are typically divided into Baritones (higher basses) and Basses, who are the lowest voice part.