JavaScript Fundamentals for React

How to use this course

Extract the ZIP, open this index.html, then open each lesson. Every lesson is inside its own folder and every lesson file is named index.html.

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Understand JavaScript, console, scripts, and why React needs it.

Learn let, const, strings, numbers, booleans, null, undefined, arrays, and objects.

Make decisions using arithmetic, comparison, logical operators, if/else, and ternary.

Write reusable logic with functions and repeat work using loops.

Master map, filter, find, includes, reduce, and keys for React lists.

Use objects for real data and destructuring for clean React props.

Copy, combine, and update arrays and objects without mutation.

Split code into files using import and export, the standard React project style.

Prepare for API calls in React using promises, fetch, and async/await.

Understand browser events before React event handlers.

Combine arrays, objects, functions, map, filter, destructuring, and template literals.