Aikido is a relatively new (gendai) Japanese martial art developed by Ueshiba Morihei based on his personal philosophy and Martial Arts.
Aikido's major influence stems from Dai-to Ryu (aiki) jujutsu, with Ueshiba having been a student of Takeda Sokaku. The discipline also has strong influences from classical weapons of Japan, those being the sword and spear.
Although Aikido is a gendai (modern) martial art having been developed following the Meiji Restoration, it still retains many koryu (old school) training methodologies; this is seen especially through the arts sword based influences. This peculiar mix of modern and old, together with the ideological and philosophical aspects associated with the art creates what some have described as an "identity crisis" for the discipline.
Since the creation of aikido, several of the founder's early students developed their own 'style' of the discipline however; at present the grandson of the founder Ueshiba Moriteru is the head of the Aikikai, the headquarters being in Shinjuku in Tokyo.
Aikido emphasizes joining with an attack and redirecting the attacker's energy, as opposed to meeting force with force, and consists primarily of body throws and joint-locking techniques. In addition to physical fitness and technique, mental training, controlled relaxation, and development of "spirit" (ki) are emphasized in Aikido training.
Training in Depth
Typically, Aikido is a non-competitive art which does not emphasize resistance being offered in training, this is typically explained in three ways:
1. Techniques being to dangerous to resist 2. Resistance disrupting the blending that is necessary to be developed in order to practice Aikido fully 3. Resistance making no difference to the execution of a technique if the technique is performed correctly
Instead, training typically consists of a warm up, followed by repeated drilling of the techniques, often with an emphasis on the underlying principle behind the technique. After this clubs may allow some randori practice, in this practice an Aikidoka is attacked by between one and eight of his fellow students (Often armed with bokken, jo or tanto) Who will typically perform one of several pre-set attacks dictated by their weapon (Or lack thereof).
Progression through the ranks
Although progression through the ranks requires different techniques depending upon the specific governing body and style of Aikido, the ranking system is typified by techniques simply being demonstrated at lower levels along with ukemi and randori being required at higher levels.
Aikido in the Wider Context
Aikido is not widely respected in other martial arts, either within sporting or self defense contexts. Their is a distinct lack of competitive Aikidoka and the non-resistant training methodologies used in class are generally not considered adequate preparation for actual combat (See Aliveness).
One exception to this is Tomiki Aikido, a style of Aikido that does involve resistance in training and does incorporate competitions.