You may already know that judo is a martial art originally created in Japan. What separates judo from other martial arts like Karate or Taekwondo, however, is that judo is designed specifically with sport competition in mind. Whereas sparring in other martial arts generally requires use of pads and other protective equipment or light contact (pulling of punches or kicks), judo techniques can be performed at full speed and full force while maintaining safety.
Judo in Japanese means “the gentle way” and is known as such because many of the techniques in judo rely on giving way to the force of your opponent. Don’t be fooled, however, by the term “gentle” Judo is an intense sport, a wonderful form of exercise, and can be adapted to serve as effective and powerful form of self-defense.
Judo techniques include throws, the most spectacular and recognizable elements of judo, as well as grappling techniques such as pins, chokes and arm locks. Perhaps most importantly, Judoka must learn to fall properly. Judo falling techniques (Ukemi) not only protects a Judoka’s precious internal organs from the powerful throws of efficacious opponents, but are also extremely useful when rollerblading, biking, free-style walking, curling, or hurdling fences.
Judo was founded by Dr. Jigoro Kano in 1882. In creating judo, Kano drew techniques from jujitsu that could be used safely in sport competition and that also subscribed the principle of Seiryoku zenyo, meaning maximum efficiency through minimum effort. According to this principle, all judo techniques are best performed when the desired effect is produced with the minimal possible expenditure of effort.
Along with seiryoku zenyo, Kano’s other underlying principle of judo is Jita kyoei - mutual benefit and welfare.
Judo is now practiced by millions of people around the globe and has been an Olympic sport since 1964.
Here is a video from the international Judo Federation (IJF) with Neil Adams giving a quick guide to Judo.