Taijitu the Tibetan designs have three or four swirls (representing the Three Jewels or the Four Noble Truths, i.e. as a triskele and a tetraskelion design), Lai Zhide's taijitu has two swirls, terminating in a central circle. The Ming-era design of the taijitu of two interlocking spirals has been reported as "yin-yang symbol" in the first half of the 20th century. The flag of South Korea, originally introduced as the flag of Joseon era Korea in 1882, shows this symbol in red and blue. This was a modernisation of the older (early 19th century) form of the Bat Quai Do used
Yin and yang yang are represented by broken and solid lines: yin is broken (⚋) and yang is solid (⚊). These are then combined into trigrams, which are more yang ("e.g." ☱) or more yin ("e.g." ☵) depending on the number of broken and solid lines ("e.g.", ☰ is heavily yang, while ☷ is heavily yin), and trigrams are combined into hexagrams ("e.g." ䷕ and ䷟). The relative positions and numbers of yin and yang lines within the trigrams determines the meaning of a trigram, and in hexagrams the upper trigram is considered yang with respect to the lower trigram, yin, which allows