South Korea is officially called the Republic of Korea. Its government is a unitary presidential constitutional republic. It has a total area of 100,210 sq km, a population of 50 million, and a very high HDI of 0.909. South Korea was the first nation to bring high speed fiber-optic internet access to every primary and secondary school worldwide. The martial art taekwondo originated in Korea. South Korean pop culture, including television shows and music, has been increasingly popular in Asia and other areas of the world, a phenomenon called Hallyu or the Korean Wave.