The belt system used by ITF Taekwondo is designed to show the progression of a student's training by using different colours.
The belt colours have a meaning, and are used as a metaphor for progression of training, based on the growth of a tree. This is further reinforced by the image of an evergreen tree which is seen on the back of every ITF Dobok. Students are expected to know the meaning of their belt colour and will be asked this at their grading.
White : Signifies innocence, that the Student has no previous knowledge of TaekwonDo.
Yellow : Signifies the earth from which the plant sprouts and takes root as the TaekwonDo foundation is being laid.
Green : Signifies the planet's growth as TaekwonDo skills begin to develop.
Blue : Signifies the Heaven towards which the plant matures into a towering tree as training in TaekwonDo progresses.
Red : Signifies danger, cautioning the student to exercise control, and warning the opponent to stay away.
Black : Opposite to white, therefore signifying maturity and proficiency in TaekwonDo. It also a symbol of the student's imperviousness to darkness and fear.
Once the student attains black belt level, their grade is shown by roman numerals on their belt. This starts with 1st degree (or dan). The highest rank in TaekwonDo is 9th degree - Grandmaster.
1st to 3rd degree's are 'Novice' black belts. The Korean term is 'Boo-Sabum' (Assistant Instructor)
4th-6th degrees are 'Expert' black belts (International Instructors, designated by black stripes on the arms and legs of their Doboks). The Korean term is 'Sabum' (Instructor)
7th & 8th degrees are Masters - the Korean term is 'Sahyun'
9th degrees are Grandmasters - the Korean term is 'Saesung'