The practice of science is one of the sciences immune coveted every champion or warrior in ancient times. They utilize this knowledge to fend off opponents sharp weapon, namely that the body does not work hacked or stabbed a sharp weapon. In the struggle, many people's fighters who have knowledge of this immune, so they escape death as a result of the bullets. But there can also be no doubt, many criminals or freebooters who also use this knowledge to support their crimes.

Note: If you want to practice where this science, then there must be a teacher.