The music of Ethiopia is extremely diverse, with each of the country's 80 ethnic groups being associated with unique sounds. Ethiopian music uses a distinct modal system that is pentatonic, with characteristically long intervals between some notes. As with many other aspects of Ethiopian culture and tradition, tastes in music and lyrics are strongly linked with those in neighbouring Eritrea, Somalia, Djibouti, and Sudan. Traditional singing in Ethiopia presents diverse styles of polyphony, (heterophony, drone, imitation, and counterpoint). Traditionally, lyricism in Ethiopian song writing is strongly associated with views of patriotism or national pride, romance, friendship, and a unique type of memoire known as 'Tizita'.