China, officially the People's Republic of China (PRC), is a sovereign state in East Asia. It is the world's most populous country, with a population of over 1.35 billion. The PRC is a single-party state governed by the Communist Party, with its seat of government in the capital city of Beijing. It exercises jurisdiction over 22 provinces, five autonomous regions, four direct-controlled municipalities (Beijing, Tianjin, Shanghai and Chongqing), and two mostly self-governing special administrative regions (Hong Kong and Macau); while claiming sovereignty over Taiwan.Covering approximately 9.6 million square kilometers, China is the world's second-largest country by land area, and either the third or fourth-largest by total area, depending on the method of measurement. China's landscape is vast and diverse, ranging from forest steppes and the Gobi and Taklamakan deserts in the arid north to subtropical forests in the wetter south. The Himalaya, Karakoram, Pamir and Tian Shan mountain ranges separate China from South and Central Asia. The Yangtze and Yellow Rivers, the third- and sixth-longest in the world, run from the Tibetan Plateau to the densely populated eastern seaboard. China's coastline along the Pacific Ocean is 14,500 kilometres (9,000 mi) long, and is bounded by the Bohai, Yellow, East and South China Seas.China is a cradle of civilization, with its known history beginning with an ancient civilization – one of the world's earliest – that flourished in the fertile basin of the Yellow River in the North China Plain. For millennia, China's political system was based on hereditary monarchies known as dynasties. Since 221 BCE, when the Qin Dynasty first conquered several states to form a Chinese empire, the country has expanded, fractured and reformed numerous times. The Republic of China (ROC) overthrew the last dynasty in 1911, and ruled the Chinese mainland until 1949. After World War II, the Communist Party defeated the nationalist Kuomintang in mainland China and established the People's Republic of China in Beijing on 1 October 1949, while the Kuomintang relocated the ROC government to its present capital of Taipei.China had the largest and most complex economy in the world for most of the past two thousand years, during which it has seen cycles of prosperity and decline. Since the introduction of economic reforms in 1978, China has become one of the world's fastest-growing major economies. As of 2014, it is the world's second-largest economy by nominal total GDP and largest by purchasing power parity (PPP). China is also the world's largest exporter and second-largest importer of goods. China is a recognized nuclear weapons state and has the world's largest standing army, with the second-largest defence budget. The PRC has been a United Nations member since 1971, when it replaced the ROC as a permanent member of the U.N. Security Council. China is also a member of numerous formal and informal multilateral organizations, including the WTO, APEC, BRICS, the Shanghai Cooperation Organization, the BCIM and the G-20. China is a great power and a major regional power within Asia, and has been characterized as a potential superpower.