东亚 (dōngyà) is more than just a pin on a map; it represents one of the world's most significant cultural spheres, often called the “Sinosphere” or
汉字文化圈 (Hànzì Wénhuàquān). This refers to the regions historically influenced by Chinese culture, including its writing system (Hanzi), Confucian philosophy, and shared artistic and culinary traditions. While each nation has a fiercely independent identity, these shared roots create a deep, albeit complex, regional connection.