React
A JavaScript library for building user interfaces out of reusable components.
1. Introduction to React
A JavaScript library for building UIs out of reusable components — what problem it actually solves, compared to plain JavaScript DOM manipulation.
2. JSX
Writing HTML-like markup directly inside JavaScript — and why the curly braces are the part that actually matters.
3. Components & Props
Passing data into a component from its parent — the mechanism that lets one component get reused with different data.
4. State with useState
Giving a component memory that persists between renders — the core mechanism behind any interactive React UI.
5. Side Effects with useEffect
Running code in response to a component rendering or its data changing — and what that dependency array actually controls.
6. Handling Events
Responding to clicks, typing, and other user interaction — the camelCase event props that connect markup to logic.
7. Conditional Rendering
Showing different markup depending on a condition — three common patterns, and when to reach for each.
8. Rendering Lists
Turning an array of data into an array of elements with .map() — and why the key prop isn't optional.