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Core APIs

The WordPress Core Application Programming Interface (API) is comprised of several individual APIs, each one covering the functions involved in, and use of, a given set of functionality. Together, these form the project interface which allows plugins and themes to interact with, alter, and extend WordPress core functionality.

   Why You Should Use The Core APIs

Using the core APIs when developing for WordPress is strongly encouraged because:

• Core APIs make building things for WordPress easier by providing hooks, actions, filters, helper functions.
• WordPress does the “heavy lifting” for you (database calls, input validation, security, form building) so you don’t have to.
• Using core APIs ensures your code will be both backward-compatible and future-proof.
• The APIs allow seamless integration into wp-admin for plugin/theme options pages, inline help documentation, etc.