PvP means Player versus Player.
In PvP, your opponents are other players rather than NPC creatures controlled by the game.
PvP on EVOWOW
EVOWOW is a PvP server. This means that encounters with players from the opposing faction can lead to direct PvP combat.
Within a faction's own territory, a player without active PvP status cannot be attacked in the same way as in areas where PvP is active.
Battlegrounds
Another major form of PvP is battlegrounds – dedicated combat zones where Horde and Alliance players compete against each other as teams.
Players above level 10 can join battlegrounds appropriate for their level. When the system gathers the required players from both factions, participants receive an invitation and are transferred to the battleground.
The objective of a battleground is not always simply to defeat more opponents. Different battlegrounds have their own objectives, such as capturing flags, bases, or other strategic locations.