One of the most distinctive features of Jamaican popular music is the regular use of the syncopated rhythm, known as skank, which emphasizes the upbeats, or offbeats, of a four-beat measure. Although skank rhythm can be played by a variety of instruments, certain ones tend to emphasize it, depending on the genre. For example, in rural mento, considered the root of all Jamaican popular music, this rhythm is most often articulated by a banjo (see above). In ska, low-range instruments, such as baritone or tenor saxophones or trombones, will emphasize the pattern. Rock steady and reggae music feature a muted electric guitar and/or a keyboard instrument, such as an electric organ or piano, playing the skank rhythm.