PvE (Player versus Environment).
In massively multiplayer games, it refers to the phases of play where the player faces enemies controlled by the computer, as opposed to PvP (Player versus Player), where the player faces characters played by real players.
PvE can be played in groups, and the objectives are generally defined by quests.
Massively multiplayer games often offer specialised servers for PvP, PvE or roleplay, sometimes with specific rules to encourage the desired style of play.
