A bokken is a Japanese wooden katana
Bokken were designed to lessen the damage caused by fighting with real swords and were used for the training of samurai warriors in feudal Japan. Bokken eventually became lethal weapons themselves in the hands of trained experts.
The bokken is used as an inexpensive and relatively safe substitute for a real sword in several martial arts such as Aikido, kendo, iaido and kenjutsu. Its simple wooden construction demands less care and maintenance than a katana. In addition, training with a bokken does not carry the same mortal risk associated with that of a sharp metal sword, both for the user and other practitioners nearby.