Model is extension for mediawiki brings "M" from MVC pattern into MediaWiki.
Very simple and lightweight thing. Model allows you use model-objects over Mediawiki DatabaseBase class.
With Model you can focus on work with objects, not SQL-queries.
$user = new Model_User();
$user->password = '1234';
$user->save();
more examples can be found here.
To start using Model:
- include it in LocalSettings.php
- create model classes based on class Model with your model description
- create proper database tables
- use models in your code.
Read documentation for additional information.