Buddhist chanting is an ancient practice that originated with the Buddha and his followers. Unlike oral rituals in many other spiritual traditions, Buddhist chants are not prayers. They arose as a way to pass down Buddhist teachings from generation to generation via the spoken word.
Chanting is used in Buddhism to purify the mind on the path to enlightenment. Chanting also serves as an excellent concentration practice for meditation and helps to calm and collect the mind. Many Buddhist chants focus upon loving-kindness, and thus they promote a positive and generous mood state.
Overview of Buddhist Chanting
Ronya Banks gives an introduction to the history, purpose, and composition of Buddhist chants in the Theravada tradition: