One such game that was a subject of such modifications, was the highly popular Fallout 4. Some modifications are so well-made that they’ve been made available for purchase or published as full-fledged games. These codes are altered by enthusiasts of the game to fix bug issues, introduce new levels or even add a new angle to the lore.

A modification, or mod, is an altered version of a game that is creating by giving a new shape to the vanilla code.