What is plainchant?
Plainchant is a style of medieval vocal music.
Plainchant sets the words of the Roman Catholic mass or prayers to music. It is sung in Latin.
Melody and harmony
The music is modal and there is a single line of melody with voices singing in unison.
Rhythm and tempo
There is no regular time signature - instead the rhythm and tempo are dictated by the words being sung.
It is performed a cappella, and would have traditionally been performed by male voices only - priests or monks.