Magento

General

• object oriented
• uses design patterns (GoF) like GRASP, but in an individual manner
• uses MVC with thin controller approach (Business Logic is mainly in Model or View), View is configured by layout XML

Technology

• PHP 7 and coding standards PSR-0 to PSR-4
• MySQL 5.6
• Apache 2.2, 2.4
• https://getcomposer.org/doc/00-intro.md PHP Composer]
• HTML5
• CSS
• jQuery
• RequireJS
• Zend Framework
• Symfony
• Magento Testing Framework
• ...

Sources

• free videos
• many Magento 2 articles
• Kindle Book 'Magento 2 Developer's Guide'