Crossfades effect in audacity software

In general crossfading means a smooth transition between one sound sample to another sound sample.

DJ’s (Disc Jockeys) often make use of the crossfading effect between musics to make sure that there is not any gaps.

In music editor software like audacity, this effect applies a fade-out to the one track and a fade-in to the another track by apply the Crossfade Tracks effect.