The Chongtong was a term for military firearms of Goryeo and Joseon dynasty. The size of chongtong varies from small firearm to large cannon, and underwent upgrades, which can be separated in three generation type. The well-known "Cheonja", "Jija", "Hyeonja", and "Hwangja" were named after the first four characters of the Thousand Character Classic in decreasing size, thus making them equivalent to Cannons A, B, C, and D.

Cannons appeared in Korea by the mid 14th century during the Goryeo dynasty and quickly proliferated as naval and fortress-defense weapons. Major developments occurred throughout the 15th century, including the introduction of large siege mortars as well as major improvements that drastically increased range, power, and accuracy.