Jujutsu is a martial art that specializes in the use of various joint locks, throws, and striking methods to manipulate and neutralize opponents balance and mobility. These techniques of combat and movement were employed by the Samurai against single, multiple and armed opponents. Still, the principles behind these methods were applied to the more peaceful side of life as a Samurai. Descendant arts include Judo, sambo, Brazilian jiu-jitsu (via judo), shooto, aikido, hapkido, bartitsu, and German ju-jutsu. Though the fundamentals of jujutsu are simple to learn, the advanced methods and techniques take years of dedicated study to master.