Ally

From Guild Wars Wiki

An ally is any creature, player or NPC, who is friendly towards you and your party. All party members are also allies. From a game mechanics perspective, each character is considered an ally of themselves (skills which target allies but cannot target yourself specify "other ally").

Allies are shown as green dots on the radar and/or with green names in the user interface in PvE, and show up with names and dots of your team's color in PvP.

Some non-party allies, such as animal companions and mission specific NPCs, will appear in your party window, below all other party members.

Allies will not be affected by spells or skills that specify "party members" instead of "allies". For some skills this isn't true, but those are believed to be bugs in the skill's wording.

An ally may also refer to a guild that is part of a Factions alliance.