Modification
From Black Mesa: Wiki
(Redirected from Mod)
A modification or mod is the product of members of the general public (as opposed to the original designers) making changes to a PC or video game. A mod can be an edited version of the base game or an entirely new game, but is not a standalone game, as mods rely on material from the original game to run. A mod can be a partial conversion, adding new content to the original game, a total conversion, creating a new game, or an unofficial patch, fixing bugs in the original.
Black Mesa is a total conversion of Half-Life 2, using the Source engine.
