Security
TopicKeeping a Drupal site secure requires monitoring security announcements, performing regular updates, and knowing how to properly use Drupal’s APIs to write secure code.
Drupal Composer Project
TopicThe Drupal Composer Project provides a scaffold for starting a new Drupal project and managing that project's dependencies with Composer. It was created before the drupal/recommended-project Composer project template was developed, which is the current best practice method for creating a new Drupal site with Composer.
YAML
TopicYAML, which stands for YAML Ain't Markup Language, is a human-readable data serialization format that's been widely adopted in a variety of use cases in Drupal.
Learn about resources to guide you through the process of updating a module or theme to the latest version of Drupal.
Themes provide the HTML, CSS, JavaScript, and other assets that are responsible for the look and feel of your site.
Drupal Core Modules
TopicA module is a set of PHP, JavaScript, and/or CSS files that extends site features and adds functionality. The Drupal core software comes with a set of modules that provide a range of features.
Introduction to Drupal
GuideTheming Cheat Sheet
GuideFrontend Theming
GuideLearn Drupal
GuideDrupal Console
TopicDrupal Console provided a command line utility for performing common site administration tasks, code generation scaffolding, and a Read-Evaluate-Print-Loop for interacting with your Drupal site.
It is no longer actively maintained. Use Drush instead.
Drupal User Guide
GuideObject-Oriented PHP
TopicObject-oriented PHP utilizes classes and objects to organize code into reusable chunks. This approach helps us organize complex applications, such as Drupal, into modular code called classes that can be reused across the entire system.
Symfony
TopicSymfony is a set of reusable PHP components, and a framework for building PHP applications. Drupal makes use of various Symfony components.
Test Custom Code
GuideKeep Drupal Up-To-Date
GuidePerformance and scalability determine how fast your application can serve a page and to how many users at a time.
Twig is a template engine for PHP, which is the language used in Drupal. Twig can be used to design templates in generic PHP applications as well as Drupal themes.
PHP namespaces provide a way in which to group related classes, interfaces, functions and constants. Drupal uses PSR-4 namespaces to autoload the correct PHP class from a file, accommodating variations in site structures.