Archaeologists unearth evidence of ancient China's advanced mastery of metals.
China exchanges ideas and techniques with the outside world.
Imperial astronomers and mathematicians keep meticulous records.
Rulers face the tension between the need to govern and the need to keep the population contented and quiet.
China tries to feed 20 percent of the world's population with just seven percent of the globe's available arable land.
China's controversial one-child policy puts the culture's fundamental values under great strain.
Many around the world look to China for new directions in health care.
During the last quarter of the 20th century, China makes a great leap of industrialization.