This section is about Audio Modulation. One example of this is Amplitude Modulation (AM). When you modulate the volume of audio with a LFO you get a vibrato effect.
This section is about MidSide processing. MidSide is an alternative way of looking at stereo. We are used to think of stereo as the combination of a left and a right channel.
This section is all about dynamics. The dynamics of an audio signal is about the range in level of the signal: from the softest whisper to the loudest explosion.