Tutorial:Modding tutorial

These tutorials range from teaching the first steps of modding to in-depth explanations of individual mechanics:

Modding tutorial/Gangsir — A simple modding tutorial that suits beginners well.
Mod structure — More details on how mods need to be structured in order to be loaded by the game.
Scripting — A small tutorial that focuses on run-time scripting and provides some info on how to use the story script.
Mod settings — A comprehensive tutorial about how to create and use mod settings.
Localisation — A tutorial about how to format and use localisation, which is how mods are translated.
Inspecting a live mod — An annotated tour of a mod that is live on the mod portal right now.
Mod changelog format — The formatting requirements for the mod changelog.txt file.
Script interfaces — A small tutorial about script interfaces (LuaRemote) and custom keyboard shortcuts.
Noise Expressions — A tutorial about generating terrain, complete with example mod.
Untitled GUI Guide — A tutorial about building custom interfaces that also expands into more advanced parts of GUI modding.

Modding FAQ
Prototype documentation
Scenario system — Save-based mods ("soft mods") and their limitations
Factorio API Documentation — Documentation of the runtime api
Migrations guide — All information about mod migrations
Factorio data github repository — Tracks changes of the lua prototype definitions in Factorio in between releases.

See also