<P> Musicology, the academic study of the subject of music, is studied in universities and music conservatories . The earliest definitions from the 19th century defined three sub-disciplines of musicology: systematic musicology, historical musicology, and comparative musicology or ethnomusicology . In 2010 - era scholarship, one is more likely to encounter a division of the discipline into music theory, music history, and ethnomusicology . Research in musicology has often been enriched by cross-disciplinary work, for example in the field of psychoacoustics . The study of music of non-Western cultures, and the cultural study of music, is called ethnomusicology . Students can pursue the undergraduate study of musicology, ethnomusicology, music history, and music theory through several different types of degrees, including bachelor's degrees, master's degrees and PhD degrees . </P> <P> Music theory is the study of music, generally in a highly technical manner outside of other disciplines . More broadly it refers to any study of music, usually related in some form with compositional concerns, and may include mathematics, physics, and anthropology . What is most commonly taught in beginning music theory classes are guidelines to write in the style of the common practice period, or tonal music . Theory, even of music of the common practice period, may take many other forms . Musical set theory is the application of mathematical set theory to music, first applied to atonal music . Speculative music theory, contrasted with analytic music theory, is devoted to the analysis and synthesis of music materials, for example tuning systems, generally as preparation for composition . </P> <P> Zoomusicology is the study of the music of non-human animals, or the musical aspects of sounds produced by non-human animals . As George Herzog (1941) asked, "do animals have music?" François - Bernard Mâche's Musique, mythe, nature, ou les Dauphins d'Arion (1983), a study of "ornitho - musicology" using a technique of Nicolas Ruwet's Langage, musique, poésie (1972) paradigmatic segmentation analysis, shows that bird songs are organised according to a repetition - transformation principle . Jean - Jacques Nattiez (1990), argues that "in the last analysis, it is a human being who decides what is and is not musical, even when the sound is not of human origin . If we acknowledge that sound is not organised and conceptualised (that is, made to form music) merely by its producer, but by the mind that perceives it, then music is uniquely human ." </P> <P> In the West, much of the history of music that is taught deals with the Western civilization's art music, which is known as classical music . The history of music in non-Western cultures ("world music" or the field of "ethnomusicology"), which typically covers music from Africa and Asia is also taught in Western universities . This includes the documented classical traditions of Asian countries outside the influence of Western Europe, as well as the folk or indigenous music of various other cultures . Popular or folk styles of music in non-Western countries varied widely from culture to culture, and from period to period . Different cultures emphasised different instruments, techniques, singing styles and uses for music . Music has been used for entertainment, ceremonies, rituals, religious purposes and for practical and artistic communication . Non-Western music has also been used for propaganda purposes, as was the case with Chinese opera during the Cultural Revolution . </P>

Name something specific that a lot of country western songs are about