Kun simply means "rules." In Shotokan circles, there are two basic well-known kun, the Dojo Kun and the Niju Kun. The Dojo Kun is believed to have been initiated by Santunuku "Tode" Sakugawa, although Gichin Funakoshi is given much credit for its present day use. The Dojo Kun is recited at the end of every Shotokan karate class, almost anywhere in the world. It consists of a simple list of 5 rules of conduct for any karateka.
English JKA translation:
Seek perfection of character
Refrain from violent behavior
Alternate English translation:
One! To strive for the perfection of character
One! To defend the path of truth
One! To foster the spirit of effort
One! To honor the principles of etiquette
One! To guard against impetuous courage
In addition to the Dojo Kun, Gichin Funakoshi later added the Niju Kun, or "Twenty Precepts." These were designed as more specific guidelines for the karateka to follow.
The 20 Precepts of Gichin Funakoshi
1. Do not forget that karate begins with rei and ends with rei.
2. There is no first attack in karate.
3. Karate supports justice.
4. First understand yourself, then understand others.
5. The spirit is more important than the technique.
6. Free the mind.
7. Trouble is born of negligence.
8. Do not think karate belongs only in the dojo.
9. Karate training requires a lifetime.
10. Put karate into everyday life, and you will find perfect existence.
11. Karate is like hot water; it cools down if you do not keep on heating it.
12. Do not think that you have to win, instead think that you do not have to lose.
13. Move according to your opponent.
14. Victory depends on proper strategy.
15. Think of the hands and feet as swords.
16. When you leave home, think that you have a million enemies awaiting you.
17. Postures are for the beginner, later it is natural body.
18. Do the kata correctly, the real fight is a different matter.
19. Do not forget control of the dynamics of power, the elasticity of the body, and speed of the technique.