The word ninja started 800 years ago in the mountains of Japan that meant someone who practiced ninjutsu (which is sometimes referred to in the west as Ninjitsu), a kind of martial art often called "the art of stealth" or "the art of invisibility".
Historical examples of ninja include Minamoto no Yoshitsune, who employed surprise as a major weapon in his victories. He is said in a popular folktale to have been educated by a tengu to learn the tactic and became a ninja.
Ninja used several special weapons against their enemies, the shuriken (throwing stars) and handclaws (shuko, tekagi) probably being the most famous. Kunai was also a popular weapon as they could be hidden easily. The makibishi, a type of caltrop made of iron spikes, is also famous. It could be thrown on the ground to injure the chaser's feet or laid down on an enemy's escape path so that the targets could be cut down or shot down with bows and arrows while they looked for another escape route, but it could also be covered with poison so the victim would die slowly. Occasionally, makibishi would be loaded with gunpowder to explode upon impact, further damaging a pursuer's foot.
There have been many spoofs of the ninja, such as Beverly Hills Ninja, Teenage Mutant Ninja Turtles, and Ninja Burger and Real Ultimate Power.
Teenage Mutant Ninja Turtles is the 1990 live-action movie based on the Teenage Mutant Ninja Turtles franchise. It had two sequels, Teenage Mutant Ninja Turtles II: The Secret of the Ooze and Teenage Mutant Ninja Turtles III: Turtles in Time. This movie kept very close to the dark feel of the original comics with only few things making it in from the cartoon.
The Turtles are depicted as more of a family than as a fighting team (unlike in the 1987 cartoon). Given that in the comics the same was true, this is a far more loyal interpretation of the Turtles. After the third season, The Shredder has apparently vanished from the cast, however, being the most enduring villain of Turtle history, it is likely he, or some new incarnation claiming the title for themself, will eventually take on the Turtles again. In addition, the series has begun becoming far more dark, progressing to a fairly dark outlook for Leonardo, starting from an adaptation of the 'City at War' storyline which in the original comics, was meant to be the Turtles' Coming of Age story. Leo has since become almost like the Turtles' own version of Batman, in that he is a far more driven individual after the events of season three. His personality has become very grim and gritty, more so than even Raphael, who was before now the turtle with the darkest personality of the quartet. He also is the only Turtle to recieve apparently lasting damage in that a piece of his shell near his left shoulder has been badly damaged.
The first film, simply titled Teenage Mutant Ninja Turtles, is one of the top-grossing independent films ever made in the United States. While fans of both the cartoon and the comic were appeased, many felt that the Turtle characters, with the exception of Raphael, seemed to have too similar of personalities. The movie's first half focuses on Raphael's character, and touched on the others. The costuming effects, a product of the Jim Henson Creature Shop, were very advanced. New puppetry techniques were innovated, later applied to other motion pictures and the short-lived sitcom, Dinosaurs.
The second film, entitled Teenage Mutant Ninja Turtles II: The Secret of the Ooze, expands on the Turtles'. It featured new characters: Shredder's mutants Tokka and Rahzar, and a mutated Super-Shredder. The original story was to include Rocksteady and Bebop at the insistence of the studio, but Laird and Eastman fought tooth and nail to prevent their inclusion, and created Tokka and Rahzar as a way of compensating. The original ending to "Ooze" would also reveal the benevolent TGRI scientest Jordon Perry who helps the Turtles (played by David Warner) to have been a Utrom, but due to budget constraints, plus the fear he may be mistaken for Krang, the plot point was dropped.
The third film in the series was Teenage Mutant Ninja Turtles III: Turtles in Time, which featured the return of the character Casey Jones, played again by Elias Koteas. The plot of this film includes the Turtles traveling back in time to ancient Japan and donning Samurai armor. The costuming was not done by Henson's Creature Shop this time because, as the story goes, Henson's thought TMNT too violent and refused. A company called "All Creature Effects" stepped in for the costuming. In an interesting reversal, all the Turtles use their weapons against their enemies.