Art music (or serious music or erudite music), is an umbrella term generally used to refer to musical traditions implying advanced structural and theoretical considerations and a written musical tradition.The notion of art music generally refers to a frequent musicological distinction that musicologist Philip Tagg refers to as an "axiomatic triangle consisting of 'folk', 'art' and 'popular' musics". As Tagg explained, each of these three is distinguishable from both others according to certain criteria. In this regard, it is frequently used as a contrasting term to popular music and folk music. (Folk music is also frequently referred as traditional music in this classification.) It is mostly used to refer to music descending from classical tradition. This is generally the common definition musicologists and scholars including Theodor Adorno, Deryck Cooke, Joseph Swain, Nicolas Cook or Nicola Dibbens and Philip Tagg refer to. However some other authors interested in music theory may define it differently. Musician Catherine Schmidt-Jones for example defines art music as "a music which requires significantly more work by the listener to fully appreciate than is typical of popular music." In her view " this can include the more challenging types of jazz and rock music, as well as Classical."[