In my college English Class, we were learning about morality as in Moral Amoral Immoral. My professor defined moral in what I thought was an unusual way, so I asked where true right and wrong come in. My professor said that was an opinion. I didn't quite understand, so I gave an example and asked again, "What about Killing, killing is always wrong, where does that come in with morality" My professor then responded, "Well, is some cultures killing is right." And that's when I understood what realism was.