Is React a library or a framework?

Direct answer

React is a library focused on building user interfaces, while a framework usually defines a broader application structure and includes more built-in solutions.

Area	React	Typical full-stack framework
Primary scope	UI components and rendering	Application structure across multiple concerns
Routing	Not built into core React	Usually integrated or prescribed
Data/loading conventions	Can be added in many ways	Often provides conventions or APIs
Project structure	Flexible	Usually more opinionated

React can be used by itself, but production applications often use it through a React framework that adds routing, server rendering, data loading, and build conventions.