Editing WoW:UI beginner's guide (section)

=== The developer's point of view ===
AddOns mainly consist of two types of files:
* [[Lua]] files, which contain the brunt of the logic
* [[XML User Interface|XML]] files, which define how your dialogs, buttons, etc look. These elements are commonly referred to as "Widgets".

You list these files in a [[The TOC Format|TOC]] (Table Of Contents) file together with some additional parameters.

If you have programmed before, you may be used to having your program start, and keep running, until you don't want it to run any more. Not so in WoW. AddOns are ''event driven'', i.e. everything that happens does so in response to an event, e.g. the user clicking one of your buttons, the client receiving a chat message, someone hitting the character, etc. Those events are delivered to widgets, and to grab hold of them, you need to embed little snippets of Lua code in the right places that calls functions in the .lua files. &nbsp; It ''is'' possible to implement a whole addon in just the .xml files, but it gets clunky, and you need to HTML-encode &lt; and &gt; characters and so forth.

Good places here on WoWWiki to look for more information:
* [[Interface Customization]]
* [[World of Warcraft API]]
* [[XML User Interface]]
* [[AddOns]] - a guide on how to create an addon from scratch
* [[:Category:HOWTOs]]
* [[XML Basic]] - needs help of pro addon developers to fill up reference

External guides:
* [http://wow.mmhell.com/articles/interface_modification/beginners_guide.html A Beginner's Guide to Interface Modification at mmhell.com] (Marian 'Fyrn' R, Aug. 2004) - out of date
* [http://wow.mmhell.com/articles/interface_modification/writing_your_first_addon.html Your first AddOn at mmhell.com] - out of date