Understanding the Body
In the study of self defense, an important topic is to better understand your body so you can use it more efficiently. The Yin Yang says there is another side, so you should equally study your opponents body - this time with an aim to make your techniques more uncomfortable for them so it does not take as much strength from you to be effective.
The section on body weapons discusses the 32 different blocking and striking surfaces on your body you can use during your defenses
The section on Pressure Points shows the 35 main points you will be aiming for on your opponent.