This document classifies and describes the different types of human voices. It divides female voices into soprano, mezzo-soprano, and contralto. Male voices are divided into countertenor, tenor, baritone, and bass. Each voice type has a defined range and tessitura. Examples of famous singers are given for each voice type. Videos are included to demonstrate the different voices. Vocal groups like mixed choirs, male choirs, female choirs, and children's choirs are also defined.