web dev//framework//React

React is a declarative, component-based JavaScript library for building user interfaces. It is frontend only: it runs in the browser, never on the server by itself.

React is a declarative, component-based JavaScript library for building user interfaces. It is frontend only: it runs in the browser, never on the server by itself.

Components return JSX (an HTML-like syntax inside JavaScript), and state changes trigger re-renders, with the browser doing all the work. In a single page application (SPA) React controls the entire page, so navigation happens on the client with no full page reloads. The full bundle is the price: for content sites Astro, which ships no JS by default and hydrates only the interactive islands, loads faster, while React suits interactive apps such as dashboards and editors.

Where React is a library for the view and leaves routing and state to other packages, Angular is a full framework that prescribes all of them. JSX only describes elements, and React updates the DOM after comparing what changed.

React needs a bundler to ship (Vite, Webpack), or a framework such as Next.js to add a backend.

InfraPhysics uses React 19 with Vite 6. All content compiles at build time to static HTML and JSON, and the browser loads React, which renders the UI. There is no backend, only static files on Cloudflare Pages, and that includes the wiki: entirely frontend, with the wikinotes compiled to JSON and the graph and search running in the browser.