Fade is a continuous transition from one state to another.
The term is used in audio and video technology for crossfading. When one audio or video signal
fades continuously to another. This isreferred to as fade-in or fade-out, depending on whether you are fading something in or out. The
function is also known from car stereos for adjusting the volume between the front and rear speakers. The potentiometers used for fading are called fade controls or faders.