Help:Lua

• Help:Lua for beginners
• Help:Lua debugging – about debugging Lua modules
• Wikipedia:Lua style guide – standards to improve the readability of code through consistency
• Module:Sandbox provides a pseudo-namespace for experimenting with Lua modules

"Hello world"

• See Module:Example

Documentation

• Scribunto Lua reference manual (Manual for the Mediawiki implementation)
• Programming in Lua (Official book/introduction to Lua)
• Lua tutorials at lua-users.org
• Wiktionary:Lua on English Wiktionary: contains notes on efficiency and on dealing with Unicode and UTF-8

How-to guides

• Help:Lua for beginners
• Wikipedia:Lua style guide – standards to improve the readability of code through consistency
• "What do converted templates look like?" (slideshow)
• Wikipedia:Lua string functions
• Wikipedia:Guide to Scribbling

Debugging modules

• Module:SimpleDebug - It allows to collect and view the values of one or several variables and/or customized labels of several points of a lua program.

Testing modules

• Module:UnitTests - used to power many module unit tests, which are usually found by the name "Module:(your-module-name)/tests".
• Module:Example/testcases – Results - Unit tests for Module:Example (the "hello world" module)

Profiling modules and functions

• Module:Timing – module to do some simple probing of timing issues, mostly to spot and fix load problems

Patterns

• mw:Extension:Scribunto/Lua_reference_manual#Patterns
• mw:Extension:Scribunto/Lua_reference_manual#Ustring_patterns
• PatternsTutorial
• REGEX (as applied by WP:AWB): WP:REGEX

Wikipedia resources

• Special:PrefixIndex/Module:Sandbox - allows you to work on a set of files within a sandbox prefix.