China, officially the People's Republic of China (PRC), is a country in East Asia. With a population exceeding 1.4 billion, it is the world's second-most populous country after India, representing 17.4% of the world population. China spans the equivalent of five time zones and borders fourteen countries by land. With an area of nearly 9.6 million square kilometers (3,700,000 sq mi), it is the third-largest country by total land area. The country is divided into 33 province-level divisions: 22 provinces, five autonomous regions, four municipalities, and two semi-autonomous special administrative regions. Beijing is the country's capital, while Shanghai is its most populous city by urban area and largest financial center.
China is considered one of the cradles of civilization: the first human inhabitants in the region arrived during the Paleolithic; by the late second millennium BCE, the earliest dynastic states had emerged in the Yellow River basin. The eighth to third centuries BCE saw a breakdown in the authority of the Zhou dynasty, accompanied by the emergence of administrative and military techniques, literature, philosophy, and historiography. In 221 BCE, China was unified under an emperor for the first time. Appointed non-hereditary officials began ruling counties instead of the aristocracy, ushering in more than two millennia of imperial dynasties including the Qin, Han, Tang, Yuan, Ming, and Qing.