Taegeuk Il Jang is considered a beginner form, often (but not universally) practiced by students of Kukki style taekwondo with rank of 8th geup.
The floor pattern of each taegeuk poomsae then represents three broken or solid lines, called trigrams or gwae (bagua in Chinese).
For this reason, the trigram associated with Taegeuk Il Jang is three solid lines ("gun") denoting "the sky" or "the heavens".
When these pioneers returned to Korea after the Japanese occupation, they incorporated forms practice into their teaching.
During the 1960s there were several efforts among these pioneers to unify their styles of martial art and create a consolidated set of forms.