It means strong and is a term for musical strength. Strength in music actually refers to intensity, and intensity refers to the degree of exertion, including the intensity of light and heavy beats and the intensity of emotion. Intensity is not volume. Although intensity often causes the volume to increase, the increase in volume does not depend on the increase in intensity.

Usually according to people's feeling of the sound, from strong to weak, then from strong to weak, it is helpful for the music to move forward, and people are more willing to listen to it, which is in line with people's listening habits. The changes in intensity stimulate people's feelings, and matching the music can create the connotation the composer wants to express.

The increase in volume mainly relies on vibration, and the strength is determined by the amplitude. Different amplitudes determine the strength, that is, the strength of the sound. But it should be noted that strong and weak sounds must be compared with more than two sounds in order to know the strength relationship between them. A single sound is neither strong nor weak.

In music, intensity is an important means of musical expression. The intensity of the beat refers to the basic strength and weakness rules of each beat. When we play and sing, we must follow the strength and weakness rules of the beat and cannot change it at will. The intensity in rhythm refers to the different intensity patterns produced by the rhythm type in each beat.

The commonly used form of intensity change in musical phrases is to first crescendo and then decrescendo, forming an olive shape. But there are also those that are strong first and then weak, those that are weak first and then strong, and those that are first weak and then strong. This change is generally consistent with the rhythm and beat structure of the phrase.