The flag's background is white, which is a traditional Korean color, common to the daily attire of 19th century Koreans and the color is also use for a traditional Korean wear (hanbok). It represents peace and purity. The circle in the middle is derived from the philosophy of yin and yang and represents the balance of the universe. The blue section represents the negative cosmic forces, and the red section represents the opposing positive cosmic forces. The trigrams together represent the principle of movement and harmony. Each trigram (hangeul: 괘 [gwae]; hanja: 卦) represents one of the four classical elements.
These four trigrams are described in the table below:
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