Kenjutsu is usually recognized as combative. It always begins with the sword already drawn with an aggressive intent. The first recorded historical systematic teachings of the Japanese long sword began about 800 AD. Since that time, over 1200 different ryu (schools) have been documented. Many exponents of kenjutsu began to question if a higher understanding could be achieved through practice and study with the sword. These kenshi (swordsmen) developed the art of the sword (kenjutsu) into a way of the sword (kendo). To signify their advances, they coined the name kendo. This divisive move began around the middle of the 14th century. Kenjutsu is considered a classical bujutsu (art of war or martial art), having been well formulated prior to the Meiji reformation (the classical/modern dividing line). Classical kenjutsu ryu (schools) tend to be quite secretive of their techniques, being very closed to outsiders. Classical kenjitsu ryu are the closest to classical warrior training in the modern world. Examples are Yagyu Shinkage Ryu, and Tenshin Shoden Katori Shinto Ryu. Kenjutsu wear is traditional, consisting usually of hakama (split skirt trousers) , keikogi (a heavy weight jacket worn tucked in) and obi (belt). As a rule, there are no belt colors in kenjutsu, but only titles; Deshi (student), Renshi (instructor), Kyoshi (teacher) and Hanshi (master). Kata (prearranged forms or exercises)are the usual way of learning the intricate motions required. Initially one practice solo, but later pairs or multiple kenshikata are performed. The standard practice tool is either a bokken (simulated wooden sword) or an actual live blade. Actual cutting, and thrusting of the blade against water soaked rolled mats and bamboo poles, called tameshigiri, give the more advanced exponent practice in actual impact of the live blade against a target.
KENDO (“the way of the sword”)
Kendo is generally considered a classical budo (martial way), being formulated before the Meiji Restoration. In its most modern from it is practiced more as a sport and to improve the mind of the individual,
rather than a form of combat. In the beginning, kendo was a technique for training in kenjutsu without the bodily consequences of mistakes inherent in bokken or live katana or tachi practice (live blades). The standard weapon of kendo is a shinai, which is a split stave of bamboo with a leather tip cap and a leather handle. There is no curvature and the shinai is quite light in weight. Traditional gi (clothes) are worn, but over this are budogu (fencing armor), similar to what western fencers wear. The men (a face mask with throat protector), the do (a breastplate), the kate (gloves and gauntlets), and a tare (heavy apron).Legal strikes are to the wrist , the sides of the do, and three cuts to the head (left right and center) and one thrust (the throat). An defined area (a square about 10 meters on a sides)is the legal mat area , and two legal strikes as called by judges are required to win a match. Advancements is done by way of kyu and dan, similar to colored belts in other martial way. But the obi (if worn, sometimes deleted) always remains the same color. At the higher dan levels one is required to show some minimal competence with a live blade in ten kata, with both long (daito, katana or tachi)and short (shoto, wakizashi) swords. Classical ryu have all but disappeared within kendo, and so the emphasis is much more on the sport aspects.
Iaido /Iaijutsu
Iai is considered a classical bujutsu or budo. It is more difficult to characterize iai , as the students progresses the –do aspects are left behind and the jutsu aspects become more pronounced. Iai is believed to have its origins about 1200 AD, with about 800 ryu cataloged since then. It is possible that the present art of iai had its origins in an ancient reference to “tachi- gake” from about 1000 AD. Iai is differentiated from the ken styles in that the sword is initially at rest in the scabbard instead of already drawn for combat. Iai is composed of drawing the sword (nukitsuke), bringing it to combative use in minimum time , and returning the sword to the saya (scabbard). Starting positions for iai can be from combative postures or from everyday setting or standing positions. Traditional gi are worn as in kenjutsu. Advancement can be either in the traditional method, without dan kyu, or can include it similar to kendo. Iai within the Zen Nihon Kendo Renmei is ranked, and several instructor credentials are also available; called renshi, kyoshi and hanshi, which are also available in kendo. The reason for the kendo federation having oversight of iaido is quite simple. Early this century, kendo practitioners were aware that kendo was not properly teaching the sword. A shinai is not a Nihon- to (Japanese sword) and does not handle like a sword. Kendo did retain ten kata as a part of their promotion process, but they were felt to be insufficient to properly teach the “way of the sword”.
In the late 1950s the Kendo Federation invited classical iai expert swordsmen to form a commission to investigate courses of action. The result was a selection and adoption of seven iai kata. This list was later revised to ten kata by a later commission. These kata formed the basis of the Zen Nihon Kendo Renmei Seitei Gata. These ten kata form the basis of kendo based iai. Further advancement is made within classical ryu. Example are the Muso Jikiden Eishin Ryu and the Muso Shiden Ryu. These two ryu are splits of the same branch and remain quite probably the most practiced ryu of iaido. These were the first to allow the public to join their ranks and participate as outsiders. The Seitei Gata have three opening positions. Seiza is used for the first three and is considered a non- combative position. Tate- hiza is used for the fourth kata and is considered neutral, that is neither combative or non- combative. Finally, the last six kata are started from tachi- ai, and also considered neutral. There is one other opening position which is considered combative but is not used in seitei, called iai- goshi. The reason for non-combative or neutral starts is that these are the positions of everyday life. One could expect a surprise attack at anytime, and the ability to react from an everyday starting position was considered essential.
Kendo is generally considered a classical budo (martial way), being formulated before the Meiji Restoration. In its most modern from it is practiced more as a sport and to improve the mind of the individual, 
Iai is considered a classical bujutsu or budo. It is more difficult to characterize iai , as the students progresses the –do aspects are left behind and the jutsu aspects become more pronounced. Iai is believed to have its origins about 1200 AD, with about 800 ryu cataloged since then. It is possible that the present art of iai had its origins in an ancient reference to “tachi- gake” from about 1000 AD. Iai is differentiated from the ken styles in that the sword is initially at rest in the scabbard instead of already drawn for combat. Iai is composed of drawing the sword (nukitsuke), bringing it to combative use in minimum time , and returning the sword to the saya (scabbard). Starting positions for iai can be from combative postures or from everyday setting or standing positions. Traditional gi are worn as in kenjutsu. Advancement can be either in the traditional method, without dan kyu, or can include it similar to kendo. I
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