I'm fairly certain that most here have seen movies of the medieval nature and there are scenes were someone is working at a forge and anvil and hammering a sword and such.

Thing is, I heard recently from somewhere that after a sword is forged, you don't repair it by reheating and hammering out the edge again and that you mostly grind with a whetstone.

How true is this? What is the actual way to repair a sword (both post battle or broken)?

I'm terribly sorry for asking this here if this isn't the correct place to do so, but trying to find information about how to repair a sword on google just consistently gives me repairing swords in a game.