There were two purposes.

1.) Slave work songs, also known a spirituals, were songs that slaves sang because of their tradition. These folksongs helped enslaved people stay connected with their religion and their family. It was a way of ‘staying sane’, if you will, while working.

2.) Another important purpose was to communicate. Since slave could not talk together for a long time, nor could they escape, obviously, they encoded plans and words that would have specific meanings. For example. a father working on a plantation with his wife and children would be singing a spiritual, and he might clap on a word. This word may have specific meaning with specific instructions. People used spirituals to escape their servitude or plan for revolts or escape.