As discussed previously, prior to Drupal 8, RESTful web services could be implemented in Drupal 7 using the Services module or RESTWS module, which (using the REST server) can be used to build powerful Headless Drupal websites. But with the evolution of Drupal 8, this functionality has been attached to the core of the Drupal 8 default bundle, along with other contributed features and modules that are pushed to the core, such as Views, Link, WYSIWYG editors, and so on.
Drupal 8 achieves the full functionality to set a basic web services environment to provide APIs using four modules in the core. They are as follows:
RESTful web services (REST): This exposes entities and other resources via a RESTful web API. It depends on the Serialization module for serialization of data that is sent to and from the API.
Serialization: This provides a service for serialization of data to and from formats such as JSON and XML.
Hypertext Application Language (HAL): This serializes...