Music is an art form and cultural activity, and its medium is sound waves (a kind of mechanical waves) organized according to time and law. Its basic elements include strength, tonality, duration and timbre. These basic elements combine with each other to form the common "formal elements" of music, such as rhythm, melody, harmony, strength, speed, mode, form and texture. The formal elements of music are the means of expression of music. Different types of music may emphasize or ignore some elements. Music is played through various musical instruments and vocal techniques, which are divided into instrumental music, vocal music (such as songs without musical instruments) and works combining singing with musical instruments. In the most general form, music is described as an art form or cultural activity, including the creation, performance, evaluation, music history research and music teaching of music works. Ancient Greek and Indian philosophers defined music as tones arranged horizontally as melody and vertically as harmony. Common sayings such as "all fields are harmonious" and "this is music in my ears" point out that music is usually an orderly and pleasant idea. But John Cage, a composer in the 20th century, thinks that any sound can be music. For example, he said, "There is no noise, only sound." The creation, expression, meaning and even definition of music vary according to different cultural and social backgrounds. In fact, throughout history, some new music forms or styles have been criticized as "non-music", including Beethoven's 1825' s big fugue, 1900' s early jazz and 1980' s hard-core punk.
Ancient Music: There is no distinction between "poetry" in ancient China, that is, literature and music are closely related. The poems in The Book of Songs, the earliest extant collection of poems in China, are accompanied by tunes and sung orally. This tradition has continued. For example, the integrated official poem in the Han Dynasty was called "Han Yuefu", and Tang poetry and Song poetry could also be sung at that time. Even now, there are pop musicians who compose and sing ancient poems, such as Su Shi's Shui Diao, which describes the Mid-Autumn Festival, and Li Bai's Thoughts on a Quiet Night. In ancient China, musicians were despised, unlike painters, because China's calligraphy and painting were closely related, and painters belonged to the literati class. In the Song Dynasty, they could even be "examiners by painting" (in fact, it was also because of Song Huizong's extreme interest in painting). Musicians have a low status and are only "actors" of aristocratic entertainment. Li Guinian, a famous singer in the Tang Dynasty, also had no political status. People know that he often appears in Tang poetry and is praised. In ancient China, the "scholar-bureaucrat" class believed that a cultivated person should be proficient in "Qin, chess, calligraphy and painting", and the so-called "Qin" is the ancient Qin that has been circulated. However, guqin is only for the exclusive use of literati and cannot be played to the public. Guqin has a low volume and is also an advanced instrument. Summary: China's ancient music theory developed slowly, and its position in the "official history" was not high, leaving no more written materials. But music, like literature, is a compulsory course for ancient intellectuals and undoubtedly plays an important role in the daily life of ancient China people. Folk songs are full of colorful melodies.