Also known as harakiri, seppuku is the ritual suicide that allowed saving face for samurai that had failed to accomplish his task. Seppuku is Japanese and means literally "cutting stomach".
There are many misbeliefs and wrong information going on about seppuku. First of all, seppuku was almost never executed by the person alone but was a ritual that needed certain preparations and at least one to assist.
When a white sheet was spread on outside, and the samurai had put on the finest cloth he had, he took his slightly round knife from it's beautiful scabbard and put on a paper or cloth around it. This was to prevent the blood coming out and ruining the visual aesthetics of the event.
Then he push the blade into his stomach, trying to avoid piercing intestine which would cause terrible pain that would make him unable to continue the procedure. Then he cuts upward and then twist the blade (!) and right. Sometimes during this procedure the assisting samurai will take a well aimed blow with his hopefully sharp katana to cut the participant's neck. Before this, pure water was splashed to the blade of katana as a symbol of purification.
It is said that common respect towards the samurai executing seppuku is seen in the time that it takes for assistant to intervene. Most respected samurais might not even have to pierce the skin when the assistant would step in. On the other hand, samurai who has not been a nice one, might have to experience several minutes the exaggerating pain of blade in his stomach.
Last known seppuku took place in year 1970 when Japanese writer, Yukio Mishima ended his life to protest against "modern Japanese weakness". This was broadcasted by Japanese TV, NHK. It is told that it took several blows to cut his head, perhaps because his neck muscles were trained so hard, or the participant didn't know how to do it well.
It is said that suicide represents some certain character of the psyche of the Japanese people. However, seppuku is no longer present in Japan and it's forbidden by law.