Photography exhibition highlights the nation's profound changes over the past four decades and the people that drove them.

In the 1980s, in an era before machines were widely used, wheat harvesters were a common sight in northwestern China. Then, in the 1990s, migrant workers flocked to areas with concentrated populations, helping China build modern cities.

When the new millennium began, with China's accession to the WTO, a wave of desire to study abroad seemed to wash over the nation's students. In the 2010s, residential environments were increasingly improved and buying a property moved to the top of most people's bucket lists.

Nowadays, people live a good life, with few, if any, real shortages. Consumerism, as a result, has taken on a new urgency.

All these trends and phenomena can be seen in photos displayed at the Phoenix Center in Beijing. Since China's reform and opening-up in 1978, the great changes that have taken place are reflected in 40 Years of Chinese Photography. The exhibition presents more than 400 photos from about 40 photographers, demonstrating the profound changes China and its people have experienced in the last four decades.

"Photography has totally transformed people's relationship with the world," says Zhu Qingsheng, curator of the exhibition and also a history professor with Peking University. "It has two important functions. One is to document what happens and the other is to express emotions of the photographer."