Why bamboo is important to the poor people of east asia?

The oldest archaeological finds of bamboo articles in China were unearthed from the remains of a primitive society that existed some 7.000 years ago in what is now Hemudu, Yuyao County, Zhejiang Province. As early as the Shang Dynasty (16th-11th century B.C), Chinese people used the bamboo for making household articles and weapons, such as bows and arrows. Before paper was invented, strips of bamboo were the most important writing medium, more widely used than silk, for example, because they were cheaper, resistant to corrosion, and more abundant. Bamboo has thus played an important part in the spread and development of traditional Chinese culture.

Maybe a horizontal because its a pattern