The regular, pleasant, beautiful and moving sounds are called musical sounds.

In Confucian music theory, sound, music and music are concepts at three different levels. The difference between sound and sound is that sound has rhythm and pitch, while sound does not. Usually the sound is called noise and the sound is called musical sound. Whether people understand music is an important sign that distinguishes humans from animals. Musical sounds usually refer to beautiful and pleasant sounds. The waveform of musical sound is regular.

What people in the Western Zhou Dynasty called "yue" means music and dance, specifically referring to different music and dance movements used in conjunction with different etiquette. Etiquette is used to distinguish between high and low, and to judge right from wrong. Music and dance are used to soothe up and down and integrate people's hearts. The ritual and music system of the Zhou Dynasty was a combination of political and artistic education. It emphasized the mutual cooperation and mutual support of ritual and music in order to fully play the role of consolidating rule and reconciling people's hearts.