Answer (1 of 14): The term “continuity error” gets thrown around a lot in reference to Trek, oftentimes erroneously.
Some of the most famous “continuity errors” can be explained with a little imagination and common sense.
WHY DOES KHAN KNOW CHEKHOV IF CHEKHOV WASN’T INTRODUCED TO STAR TREK UNTI...
Enterprise established it as a result of Klingons experimenting with human augment DNA and it getting out of hand. It probably didn’t need to be addressed in universe, but I thought it was a fun retcon.