What constitutes a spoiler?

[AintNoSin]

I've searched for a similar thread and didn't find it. If there is already a thread about this, feel free to do whatever is a appropriate.

I think people get way too sensitive on the subject of spoilers, seeming to think that any morsel of information about the plot, even if it's a 35-year-old movie, is a spoiler and you're a bad person for revealing it and ruining the whole film for them.

I think for something to be a spoiler, it has to be something that is meant to be surprising or the object of suspense for the audience. So for The Empire Strikes Back, for example, there are only three pieces of information that I would consider "spoiler material," and that's it.

1. Lando betrays Han and Leia
2. Lando switches sides again and helps Leia escape.
3. Vader is Luke's father.

I can't think of any other piece of information about that movie that would have "ruined" it for me.