Mod

A mod (short for modification) is a piece of unofficial code that is injected into the game for the purpose of modifying its behavior. They can be used to enhance the game by means ranging from fixing bugs, adjusting core mechanics, to completely revamping the way the game is played with unique features.

The term mod is short for modification. Within the Minecraft community, the term is conventionally used in a strict sense to refer to unofficial, community-made code alterations that require third-party mod loaders. Under this definition, "mods" are distinct from officially supported game customization features, such as data packs, resource packs, and add-ons.

In the broader video game industry, the term "mod" is often used as an umbrella term for any user-created content that alters a game's look or behavior. Because Minecraft is a unique case that supports both unofficial modification and official modification APIs simultaneously, the community generally maintains a practical distinction to avoid confusion between the two methods.