Image via WikipediaChina's business and financial centre, Shanghai, is hosting the World Expo, which opened to massive crowds on Saturday.
The following is a fact file on the event, also known as the World's Fair:
WHAT IS IT?: Organisers call it the Olympics of science, technology and ideas. The main attractions are country pavilions where governments promote their values, culture and achievements.
THEME: Each Expo chooses a universal theme relevant to the future of humanity. Shanghai will look at urbanisation with the theme "Better City, Better Life".
DURATION: Six months, May 1 to October 31.
PARTICIPATING COUNTRIES: 189
VISITORS: Up to 100 million are expected.
CHINESE VISITORS: 95 percent of visitors are expected to be Chinese.
BUDGET: Shanghai has spent 400 billion yuan (58.6 billion dollars) in direct and indirect investments preparing for the Expo, according to state media -- more than was spent on the Beijing Olympics. But the Shanghai government only confirms its budget for the site is 28.6 billion yuan.
TICKETS: 160 yuan (23.50 dollars)
STATE VISITS: 20 world leaders were in Shanghai for the opening ceremony, but about 100 are expected to visit throughout the Expo.
SITE: 5.3 square kilometres (two square miles), more than twice the size of Monaco.
FREQUENCY: Expos have two categories: Large-scale "Universal Expositions", like the one in Shanghai, are held every five years, but smaller "International Expositions" can take place in between.