Chữ Hán is the term for Chinese characters in Vietnamese. Chữ Hán are used to write Literary Chinese and Sino-Vietnamese vocabulary in the Vietnamese language. They were officially used in Vietnam after the Red River Delta region was incorporated into the Han dynasty and continued to be used until the early 20th century where usage of Literary Chinese was abolished alongside the Confucian court examinations causing chữ Hán to fall into obscurity.

Jiaozhi, or Vietnamese: Giao Chỉ, was a historical region ruled by various Chinese dynasties, corresponding to present-day northern Vietnam. The kingdom of Nanyue set up the Jiaozhi Commandery an administrative division centered in the Red River Delta that existed through Vietnam's first and second periods of Chinese rule. During the Han dynasty, the commandery was part of a province of the same name that covered modern-day northern and central Vietnam as well as Guangdong and Guangxi in southern China. In 670 AD, Jiaozhi was absorbed into the Annan Protectorate established by the Tang dynasty. Afterwards, official use of the name Jiaozhi was superseded by "Annan" (Annam) and other names of Vietnam, except during the brief fourth period of Chinese rule when the Ming dynasty administered Vietnam as the Jiaozhi Province.