Aikido, is a Japanese martial art developed by Morihei Ueshiba as a synthesis of his martial studies, philosophy, and religious beliefs. Aikido is often translated as "the Way of unifying (with) life energy" or as "the Way of harmonious spirit." Ueshiba's goal was to create an art practitioners could use to defend themselves while also protecting their attacker from injury.
Aikido is primarily a grappling art in which attacks are neutralised with various types of throws or joint locks. Aikido techniques are intended to be implemented after first blending with the motion of the attacker, so that the defender may redirect the attacker's momentum without directly opposing it, thus using minimum effort. (http://www.changsmartialarts.com/home)