Vocal percussion is the art of creating sounds with one's mouth that approximate, imitate, or otherwise serve the same purpose as a percussion instrument, whether in a group of singers, an instrumental ensemble, or solo.
In Western music
Recent musicological research points at Brazilian songwriter and musician Marcos Valle as a pioneer of vocal percussion. In the track "Mentira" from his 1973 album "Previsao do Tempo", Valle emulates a drum kit with his voice by performing one repeating pattern and one fill.
Beatboxing is one school of vocal percussion, originating in hip-hop music and often used to accompany rapping. Many college and professional a cappella groups use vocal percussion to replace instrumental backing, often creating sounds not found in any physical instrument. When it is used to imitate drumset sounds, vocal percussionists use three basic effects: bass drum, snare drum, and cymbal. Variations on these sounds can be used to approximate other elements of a drum kit. A pitched bass drum is used to replace a floor tom; cymbal sounds can either be made short like a high hat (employing a sharp ts-ts-ts sound) or long like a crash or ride cymbal (attacked with a psh or a ksh sound).
In Non-Western music
Vocal percussion is also an integral part of many world music traditions, most notably in the traditions of North India (bols) and South India (solkattu). Syllables are used to learn percussion compositions, and each syllable signifies what stroke or combination of strokes the percussionist must use.
The art of speaking these syllables is called konnakol in South India, and traditional dance ensembles sometimes have a dedicated konnakol singer, although this practice is now waning. At one time it was a very respected art form, with many masters and singers.
In North India, the practice of reciting bols is usually limited to the percussionist reciting the composition about to be played, often in the context of a longer solo. These recitations are also sometimes spoken by a Kathak dancer.