WordPress Core
The official open-source software package that provides the foundational CMS functionality — admin dashboard, editor, user system, and REST API.
WordPress Core is the base software that powers every WordPress site. Think of it like the engine in a car — plugins and themes are the accessories and paint job, but Core is what actually makes the thing go. It ships with the admin dashboard, the block editor, user management, media handling, the REST API, and the entire hook system that plugins and themes rely on.
When you download WordPress from wordpress.org, that ZIP file is Core.
How It Works
Core lives in a handful of directories and files at the root of your WordPress installation. The critical ones: