In the 12th and 13th centuries, Muslim conquests throughout India divided Indian classical music into two systems that persist today, north (Hindustani) and south (Carnatic). in South India the raga-"the collection of pitches a performer may use in a piece-is more closely connected to worship. In both systems the performer tries to make the raga "characteristic of the emotion it seeks to establish" through improvisation-and with the "72 basic scales and more than 500 derived forms" that are available within the South Indian raga system, the performer has a wealth of options. Liner notes include an overview of the South Indian musical system; descriptions of traditional instruments such as the gottuvuadyam, mridugam, and tambura; track notes with notated musical analysis; and pictures of the performers and instruments.