Records of the Three Kingdoms is an official history, while Romance of the Three Kingdoms is a novel.
Tips
usage
正史 is the history the court wrote and approved. Its opposites are 野史, unofficial histories written privately, and 演义, historical novels that mix history with invention.
history
In the Qianlong reign of the Qing dynasty the court fixed the list of official histories at twenty-four, from 史记 to 明史. Together they are called the 二十四史.