From Wikipedia, the free encyclopedia.
An expansion pack is an addition to an existing computer game. These add-ons mostly add new game areas and/or an extended storyline to a full, already released game. The changes these packs do to the original game differ. Expansion packs are being developed by professional game companies and are not free, which is the difference to game mods.
An example of an expansion pack is Blue Shift for Half-life which lets the player see the happenings during the original game through the eyes of a member of the security personel rather than the eyes of a scientist (as in the original Half-life game).
