React is a JavaScript library framework for building user interfaces.
React is a declarative, efficient, and flexible JavaScript library for building user interfaces. It lets you compose complex UIs from small and isolated pieces of code called “components”.
A React component is a bit of code that represents a piece of the page. Each component is a JavaScript function that returns a piece of code that represents a piece of a web page.
Your React codebase is basically just one large pile of big components that call smaller components.
A React component is a single object that not only outputs HTML like a traditional template would, but also includes all the code needed to control that output.
The five key concepts are:
- Components
- JSX
- Props & State
- The Component API
- Component Types
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