Kendo is derived from the Japanese Samurai's dedication to the Japanese art of swordsmanship (Ken-jutsu). Training with a sword that has a live blade, as can be imagined, is very dangerous so various schools of swordsmanship in Japan's past developed ways to lessen the danger. These methods are the origin of Kendo.One weapon introduced as an alternative to the Katana (The Japanese sword used by samurai) was the bokuto, a wooden sword used in kumitachi or seiho now known as kata (set forms).
This though did still not allow for fully unconstrained practice as a bokuto was still dangerous if contact occurred, capable of breaking limbs or even killing. For this the second weapon used in Kendo was developed, the bamboo foil or shinai. Gradually the armour for use with the shinai was refined, resulting in the equipment we use today.
As mentioned above kendo today consists of two parts:
Where the participants wearing no armour use the bokuto (wooden swords), following a series of set patterns, the Kata, each using different techniques of basic swordsmanship. The kata of kendo today are ten in number, seven using the long swords and three using the short sword against the long sword. These then are the essence of the over 300 classical schools of swordsmanship (koryu). They are pretty much the same as they were when they came into existence being standardised in 1912 by the Dai Nihon Butokukai (the controlling body for Japanese martial arts at the time).
The moves taught in kata of attack and counter attack, using a teacher and student method, is the basis of the moves used when training with the shinai. The kata though stands in it's own right, as an important part of kendo, being closer to the original teaching of swordsmanship and forming an integral part of kendo grading today.
Where participants wearing protective body armour use shinai (bamboo foils) to learn attack and counter attack techniques, leading to free practice and eventually competition. Unlike kata where the bokuto is solid, competitive kendo uses a shaped cylinder of four pieces of bamboo tied together as a substitute for the real sword. This is the Shinai.
The four target areas of the body are protected by a padded mask with a metal grill to protect the face (Men), a heavy breastplate of bamboo slats and rawhide to protect the trunk of the body (Do) and padded gauntlets for the hands and wrists (Kote), as well as a padded thigh protector (Tare). The four targets are the top of the men, the sides of the do and the wrist part of the kote, a validated strike to one of these three areas must be made by a cutting action only, the fourth target area is the exception, being a thrust (tsuki) to the throat, which is protected by a small pad at the base of the men [tsuki bu]. These strikes and thrust are referred to as datotsu
NB. In shinai kendo a tsuki is made to above mentioned throat area only, whilst in kata there are several places on the body where the tsuki can be aimed at.