The History and Truth of the Three Kingdoms

The gap between the Romance of the Three Kingdoms and real history:

Zhang Yide: In the official history, Zhang Fei's courtesy name was Yide, not Yi德as in the novel.

Swearing Brotherhood in the Peach Garden: The official history did not mention that Liu Bei, Guan Yu, and Zhang Fei had sworn to be brothers, only mentioning that they were as close as brothers.