Upgrading is the process of moving your site from a previous major version of Drupal to a newer version, for example from Drupal 7 to Drupal 11.

Responsive web design is a set of design approaches and development best practices that ensures that a web design can be used on many types and sizes of devices.

Modules are bundles of primarily PHP code that extend Drupal in order to add new features or alter existing functionality.

Entities are the fundamental building blocks that make up any Drupal site. Having a good understanding of the Entity system is an important part of ensuring the data model of your Drupal site is set up properly.

Patches are used to describe modifications made to one or more code files, and can be used to share those changes.

Drupal includes the PHPUnit testing framework. This enables us to write unit and functional tests to attempt to minimize the number of bugs in our application.

In order to run a Drupal site, the web server you are using must meet minimum technical requirements.

Drupal's vendor-agnostic database abstraction layer provides an API that can query different underlying databases.

Tools and workflows for deploying code and configuration changes from one environment to another with Drupal-specific considerations.

Coding standards provide a set of rules for how your code should be formatted, and best practice guidelines for naming conventions and the location of files.

The process for keeping Drupal core and contributed modules and themes up to date with the latest security and minor version releases.

Learn about Drupal’s configuration system and how to manage configuration with both the administrative user interface and command-line tools.

PHP: Hypertext Preprocessor (PHP) is a popular interpreted programming language that is especially suited for web development. Drupal core and all contributed modules are written in PHP.