The phrase "knights and knaves" refers to a logic puzzle where a group of individuals are divided into two types: those who always tell the truth (knights) and those who always lie (knaves). In order to solve the puzzle, one must determine which type each individual belongs to based on their statements. There are several synonyms for knights and knaves that can be used interchangeably in this context. These include "truth-tellers" and "liars," "honest people" and "dishonest people," or even "angels" and "devils." Regardless of the terminology used, the aim of the puzzle remains the same: to accurately identify which individual is telling the truth and which is lying in order to solve the problem at hand.