China's rural population is over 700 million (700,000,000). A fact which remains relatively mis-understood with foreigners who have only experienced China's western-class cities, such as Beijing and Shanghai, or viewed the magnificence of the Olympics.
The rural population makes the back-bone of China's cheap work-force. These people literally self-sustaining living off the land growing their own rice, pigs, chickens, cows, vegetables, etc. Their homes have no modern-heating nor refrigeration, flooring is minimal, and often roads unpaved.
They work in factories so as to accumulate enough wealth to return home, get married and raise a family; or to support their own family members.
A lot put much pressure (and money) on their children to do well in school so they can get a desk-job, and find a good husband/wife.
So far, China has done a great job in improving their lives. For example a decade ago, the rural population would have been larger by 150 million people.
The only way to improve the lives of these people is through the development of China's economy, infrastructure and education system. Over the coming 30 years, many of these factories will be relocated to poorer-countries or automated as the rural population continues to shrink.