The flag of China, also known as the Five-star Red Flag, is a red field charged in the canton (upper corner nearest the flagpole) with five golden stars. The design features one large star, with four smaller stars in a semicircle set off towards the fly (the side farthest from the flag pole).

The red represents the communist revolution; the five stars and their relationship represent the unity of the Chinese people under the leadership of the Communist Party of China (CPC). The first flag was hoisted by the People's Liberation Army (PLA) on a pole overlooking Beijing's Tiananmen Square on 1 October 1949, at a ceremony announcing the establishment of the People's Republic of China.

More Info: en.wikipedia.org