Using the WordPress REST API #Using the WordPress REST API
API Setup : WordPress already provides a rich set of tools and interfaces for building sites, and you should not feel pressured to use the REST API if your site is already working the way you expect. You do not need to use the REST API to build a WordPress theme or plugin.
However, if you do wish to write your theme, plugin, or external application as a client-side JavaScript application, or a standalone program in a language other than PHP, then your application will need a structured way to access content within your WordPress site. Any programming language which can make HTTP requests and interpret JSON can use the REST API to interact with WordPress, from PHP, Node.js, Go, and Java, to Swift, Kotlin, and beyond.
Even if you’re using vanilla JavaScript or jQuery within a theme or plugin the REST API provides a more predictable and structured way to interact with your site’s content than admin-ajax, enabling you to spend less time accessing the data you need and more time creating better user experiences.
If you want a structured, extensible, and simple way to get data in and out of WordPress, you probably want to use the REST API.
For all of its simplicity the REST API can feel quite complex at first, so in this handbook we will attempt to break it down into smaller components to explain each part of the full puzzle.
Next Steps #Next Steps
Familiarize yourself with the key technical concepts behind how the REST API functions.
Learn more about how to interact with API resources and query for specific data in the Using the REST API section.
Once you’re comfortable with the default workings of the default routes and methods, discover how to add new data to the API or enhance and manipulate existing response objects in the Extending the REST API section.
For a comprehensive overview of the resources and routes available by default, review the API reference.