Guided Notes

Introduction to React

What React is, how it updates the page, setting up a project, and your first render.

What is React?

Slide 1 / 5

React is a JavaScript library for building user interfaces, created at Facebook (now Meta) and released as open source in 2013.

Instead of writing step-by-step instructions to change the page, you describe what the UI should look like for the current data, and React makes the page match.

UIs are built from components: small, reusable pieces such as a button, a card, or a whole page. It's a library, not a full framework β€” routing and data fetching come from add-ons or frameworks like Next.js.