Described simply, the vibrating movement of the vocal folds is an alternate opening and closing of the vocal fold edges against each other. The result of this continuous opening/closing cycle is a disturbance of molecules in the air column that lives in the throat. This disturbance in the air is known as a “sound pressure wave” or simply “sound”. Like the waves on the ocean on a windy day, the vibrating motion of the vocal folds is very complex. This is due to the constant interplay between air pressures, body tissues vibrating and resonances and echoes in the throat and mouth. You can look at some great videos of vocal folds vibrating on the internet.