Ninjutsu : Definition and history

Ninjutsu, the "art of stealth", is a system of fighting techniques, intelligence gathering, and psychological warfare that has been practiced for over nine hundred years. Made famous by the ninja spies and commandos of feudal Japan, ninjutsu is one of the most all-encompassing arts of self-protection in the world.
The art of ninjutsu actually had its most extensive use in the four hundred years of the thirteenth through seventeenth centuries in Japan. During this period of civil turmoil, the mystical art of the ninja was refined to a deadly science of individual war tactics. When the odds were too great, or honor was at stake, the powerful determination of the ninja could be hired. If it were necessary to help bring luck and restore the balance of society, ninja would take the roles of spies, assassins, body guards, or saboteurs. Many times, a Japanese commander would rely on a few black-garbed ninja to do what it would have taken hundreds of armored soldiers to accomplish.
From the mountainous regions of south central Japan, there developed two primary schools of ninjutsu - the Iga and Koga systems. From these two organizations sprang many family-administered schools of ninjutsu, each having their own specialties or secrets.
Historically, ninjutsu was a profession inherited at birth. From infancy, the ninja was conditioned to be constantly aware of the things surrounding him. As the children of ninja families grew, they were slowly exposed to the family secrets, and the ninjutsu tradition. At age five or six, the children's play activities began to take the form of training exercises. Games stressing balance and agility were introduced. At age nine, body conditioning for muscle limberness and joint flexibility was stressed. As the child matured, striking and kicking techniques were practiced against targets of bundled straw. From this training, the child ninja progressed into unarmed combat technique, and then into the fundamentals of swordsmanship and the use of the wooden staff and cane.