Taekwondo is divided into ten grades and nine dan.

1, 10th grade for white belt: indicates a blank, no knowledge of Taekwondo at all, implying an introductory stage.

2, 9 level for white belt with yellow bar: indicates a level between white belt and yellow belt, implying initial contact to start the initiation.

3, level 8 is yellow belt: indicates the earth, grass and trees take root in the earth, implying the basic stage of learning.

4, 7 level is yellow belt with green bar: indicates the level between yellow belt and green belt, the practitioner's skill is rising.

Grades 5 and 6 are green belts: indicating grass, growing green grass, implying a stage of progress in technique.

Grades 6 and 5 are green belt with blue bar: indicates the transition belt from green belt to blue belt, the practitioner's level is between green belt and blue belt.

7 and 4 levels are blue belts: indicating blue sky, the grass and trees thrive toward the blue sky, implying that the progress has reached a fairly high stage.

8, Level 3 is blue belt with red bar: indicates that the practitioner's level is slightly higher than the blue belt and slightly lower than the red belt, between the blue belt and the red belt.

9. Level 2 is a red belt: it indicates danger and has become quite powerful, implying self-restraint as well as cautioning the opponent.

10. Level 1 is a red belt with a black bar: it means that after a long period of systematic training, the practitioner has completed all the courses before level 1 and starts to move from red belt to black belt.

Division of Ranks:

Promotion from 1st to 3rd rank:

Organized by regional 1st rank group members.

Promotion four to seven dan:

by the National Taekwondo Association unified organization.

Promotion above 8th dan:

Uniformly organized by the Promotion Examination Committee of the World Taekwondo Federation or the National Institute of Technology.

The above reference? Baidu Encyclopedia-Taekwondo Ranks