Drupal 8 has introduced many new technologies, but embedded in this mix are some Drupal-centric innovations, such as the Plug-in system. In Drupal 7, there were also 20 possibilities and everything was custom. Now, it's this big unification. You just have to learn one single idea and you can apply it anywhere.
Drupal 8 has 200+ new features, setting the standard for groundbreaking ways to deploy content and ease-of-use.
Drupal provides out-of-the box tools that you can use to build your own plug-ins types and better understand the plug-in system.