South Korea (Korean: 한국/韓國, RR: Hanguk; literally 남한/南韓, RR: Namhan, or 남조선, MR: Namchosŏn in North Korean usage), officially the Republic of Korea (ROK; Korean: 대한민국/大韓民國, RR: Daehan Minguk), is a country in East Asia, constituting the southern part of the Korean Peninsula[10] and sharing a land border with North Korea. The name Korea is derived from Goguryeo, which was one of the great powers in East Asia during its time,[11][12][13][14] ruling most of the Korean Peninsula, Manchuria, parts of the Russian Far East[15] and Inner Mongolia[16] under Gwanggaeto the Great.[17] Half of South Korea's over 51 million people live in the Seoul Capital Area, the fourth largest metropolitan economy in the world.[18] The Korean Peninsula was inhabited as early as the Lower Paleolithic period. Its first kingdom was noted in Chinese records in the early 7th century BC. Following the unification of the Three Kingdoms of Korea into Silla and Balhae in the late 7th century, Korea was ruled by the Goryeo dynasty (918–1392) and the Joseon dynasty (1392–1897). The succeeding Korean Empire was annexed into the Empire of Japan in 1910. After World War II, Korea was divided into Soviet and U.S.-administered zones, with the latter becoming the Republic of Korea in August 1948. In 1950, a North Korean invasion began the Korean War and after its end in 1953, the country's economy began to soar, recording the fastest rise in average GDP per capita in the world between 1980 and 1990. The June Struggle led to the end of authoritarian rule in 1987 and the country is now the most advanced democracy and has the highest level of press freedom in Asia.[19][20] South Korea is a member of the OECD's Development Assistance Committee, the G20 and the Paris Club. South Korea is a highly developed country, ranked the third highest in Asia after Singapore and Japan.[21][22] It has the world's 12th-largest economy by nominal GDP. Its citizens enjoy one of the world's fastest Internet connection speeds and the most dense high-speed railway network. The country is the world's 5th largest exporter and 8th largest importer. Since the 21st century, South Korea has been renowned for its globally influential pop culture, particularly in music (K-pop), TV dramas and cinema, a phenomenon referred to as the Korean Wave.[23][24][25][26][27]