Judo, literally meaning "gentle way" or "way of softness", is a modern martial art, practiced primarily as a sport, and is a form of grappling. It contains substantially the same emphasis on the personal, spiritual, and physical self-improvement of its practitioners as can be found throughout gendai budo.

Judo was created by Kano Jigoro 1860–1938, at the end of the 19th century. Kano was a brilliant martial artist educated at the Tokyo Imperial University. The combination of martial talent and formal education enabled Kano to take the koryu martial arts he learned (specifically Kito-ryu and Tenjin Shin'yo-ryu jujutsu), and systematically reinvent them into a martial art with an emphasis on freestyle practice and competition. Kano devised a powerful system of new techniques and training methods, which famously culminated on June 11, 1886, in a tournament that would later be dramatized by celebrated Japanese filmmaker Akira Kurosawa (黒沢 明 Kurosawa Akira, 1910–1998), in the film "Sanshiro Sugata" (1943). In that tournament, fifteen of Kano's students faced fifteen students from a rival jujutsu school. The result was two losses, one draw, and twelve victories for the judo students.

Judo became an Olympic sport in 1964, and has spread throughout the world. Kano Jigoro's original school, the "Kodokan", has students worldwide, and many other schools have been founded by Kano's students. Of particular note is Brazilian Jiu-Jitsu, which traces its history back to Kodokan judo practitioner Mitsuyo Maeda (1880–1941), who emigrated to Brazil in the early twentieth century and taught his judo there. Today, Brazilian Jiu-Jitsu is a practice distinct from Olympic judo, which is the predominant form of judo practiced.