Modding, in the videogame world, is adding, altering, or purging content on a videogame, especially on the pc. Mods can be quests, items, houses for the player, towns, shops, factions, or altering technical stuff(scripts, textures, meshes). There are also total conversion mods, which are mods to an insane degree
A notable moddable game is Oblivion, but beware, buying this game means you will sell your soul(assuming gamers have souls)
Modding...destroying the lives of unsuspecting gamers ever day
The act of changing a game to make it another, or add features previously unavailable, old, or previously nonexistant. It is commonly done in PC games.
Despite popular belief, modding IS NOT simply changing attacks of characters such as in RTS games or making them available to create, also in RTS games.
REAL modding is changing models and/or making new models.
I was modding Battle For Middle Earth 2 by changing Sauron's attack when some one told me real modding was making new models to add into the game.