"Tae Kook" is the Korean flag. "Tae Kook" means "the origin of all things in the universe". The circle in the centre of the flag is divided into portions of red and blue by a horizontal 'S'. These red and blue portions symbolise the 'Um and Yang' theory of eternal duality which exists within nature (e.g., heaven and earth, light and darkness; hot and cold; being and not being). In science, this theory can be represented with the symbols '+' and '-'. These dualities exist as a principle of the universe.
The four "Gye" (bar designs), in the corners of the flag are based upon the Um and Yang principle of light and darkness. The location of these Gye represent the four points of the compass.
Ee-Gye, in the lower left corner, indicates dawn and early sunlight as the sun rises in the east.
Kung-Gye, in the upper left, represents bright sunshine when the sun is in the south.
Kam-Gye, in the upper right corner, symbolises twilight as the sun moves to the west.
Kon-Gye, in the lower right, indicates total darkness when the sun is in the north. Together these symbols express the mysteries of the universe.