Patch

Patches are modifications to a game that are released by the game's official creators or publishers. They add and/or change content. They are generally understood to be fixes or small changes, rather than large additions (which fall under Downloadable content|downloadable content), but the distinction is not always well-defined.

Types of Patches

Content

Content patches are patches that expand upon the content of an existing game, by adding or unlocking additional scenes, interactions, etc. Separately purchased content patches are called DLC. Patches that are included for free that include content are often also called content updates. Patches that include material not suitable for regular distribution due to sexual or otherwise explicit content are called 18+ Patches. Content patches that are not official or are consumer made are called Mods. Significant content updates may also be called expansions, add-ons, or (again) DLC.

Hotfixes

Non-intrusive patches and in-game changes to software are called hotfixes. They are used to improve performance, fix bugs, or otherwise correct errors.

Translation

A translation patch or localization patch is a patch intended to change the content and assets of a game or other piece of software so that it supports another or additional languages. Translation patches that are made by unauthorized parties are called fan translations. This is not to be confused with a game that is re-released in a different language, which is a localized version.