Technology & Coding

JavaScript Fundamentals

Go from your first variable to working with the DOM and async code you can actually reason about.

This course is for members

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What you will learn about JavaScript Fundamentals

The 7-day sprint
  1. Values, Types, and Variables. A JavaScript program is a series of values you create, name, and then use again later.
  2. Operators, Expressions, and Coercion. Operators combine values into expressions, and JavaScript will quietly convert types unless you stop it.
  3. Control Flow: Choices and Loops. Conditionals let your program pick a path, and loops let it repeat work without repeating code.
  4. Functions, Parameters, and Scope. A function packages a piece of behavior under a name so you can run it with different inputs and get a value back.
  5. Objects, Arrays, and References. Objects group related values under keys, arrays hold ordered lists, and both are handled by reference rather than copied.
  6. The DOM and Events. The browser exposes the page as a tree of objects you can read and change, and it tells you when the user does something.
  7. Asynchronous JavaScript and the Event Loop. JavaScript runs your code on one thread and handles waiting by queuing callbacks, which is what promises and async/await organize.
The 80/20: the 6 concepts that matter most
  • Values, bindings, and mutation versus reassignment
  • Functions as values, and closures
  • Array methods over manual loops
  • Truthiness, strict equality, and safe defaults
  • The event loop, promises, and async/await
  • The DOM as objects, and events as callbacks
The core idea, explained like you are 5

Everything in JavaScript is a value, and a variable is just a name tag pointing at a value, not a container holding it.

Then the quiz and the ladder

10 questions that correct you when you are wrong, and beginner, intermediate, advanced levels, each with a practical exercise.

Created Sep 12, 2026. No mistakes have been reported by learners.

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