Camper - Someone who stays in a specific area for the purpose of killing NPCs which carry valuable resources, or an area where they can repeatedly kill lower level players.
Griefer - Someone who gains pleasure from your displeasure, often a higher level player killing lower level players.
Gank - The unfair killing of a player by a stronger player or group of players.
If you are going to join a PvP server there are a few points you should be aware of.

It will take you longer to gain levels.

You will die often.

Your death will not always be a fair one.

Expect to hear trash talking.

It's kill or be killed, trust no one.
So far there is no real reward or penalty for a Player Kill, but this may change as Age of Conan matures.