You can use them to complement visual fading, slowly fill the scene with music, or stop sudden and awkward changes in sound design. Sound fades, thanks to which audio becomes progressively quieter or louder, are also two of the most popular techniques today. Fade-in and fade-out in a video are almost mandatory techniques to know at this point, but what about music? Its counterpart, fade in, works in an exact opposite way, meaning a black screen slowly becomes a picture.
