React
In depthFramework
Also known as: React.js, ReactJS
Meta’s UI library built on components and a virtual DOM. By far the most popular frontend choice.
React, explained
Written by EduVerseWhat it is
React is a JavaScript library from Meta for building user interfaces out of components: small functions that take data (props) and return what should appear on screen, usually written in JSX, which looks like HTML inside JavaScript. When the data changes, React works out what to update in the page.
Why teams use it
Updating the page by hand with JavaScript gets messy as an app grows. React lets you describe what the screen should look like for the current state and handles the updates, and components make pieces reusable. It only covers the view, so you pick routing and data fetching yourself or use a framework like Next.js.
An example from work
The cart badge doesn’t update when you add a product. You open CartBadge.tsx and find it keeps its own copy of the count in useState. The fix is a classic React lesson: state that several components share belongs in a common parent or a context.
Our own explanation, not a quote from the book.
In the book
Sentences from The Software Realm, Decoded that mention React, exactly as printed.
3 more passages about React in the full book
Read every conversation where React comes up, with the interactive slides and demos.
Where it fits
Single-page applications, component-based user interfaces
Coverage in the book
Covered in depth: multiple pages with explanations, examples and simulations.
