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Manjunath k
Manjunath k

Posted on • Originally published at mankal-27.github.io

I Built an Interactive JS Learning Site — No Courses, No Paywalls, Just Animated Examples

I got tired of JavaScript tutorials that teach you syntax in a vacuum.

You read about filter(), you nod along, and then you open a real project and think — okay but when do I actually use this?

So I built Fork My Brain — a free, open-source, interactive JS reference where every method comes with animated, real-world scenarios instead of dry theory.


What it looks like in practice

The first module is all about JavaScript Array Methods — all 41 of them (37 instance methods + 4 static).

Instead of showing you filter() with [1, 2, 3], I show you a shopping cart:

const cart = [
  { name: 'Shoes', price: 2499 },
  { name: 'T-Shirt', price: 799 },
  { name: 'Hat', price: 399 },
];

// Get only items under ₹1000
const budget = cart.filter(item => item.price < 1000);

// Apply 10% discount to everything
const sale = cart.map(item => ({
  ...item, price: item.price * 0.9
}));

// Calculate total
const total = cart.reduce((sum, item) => sum + item.price, 0);
// → ₹3,697
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Real data. Real use case. The kind of code you'd actually write.


The 5 scenarios in the Array module

Each scenario teaches a natural cluster of related methods:

  • 🛒 Shopping cartfilter, map, reduce (the holy trinity)
  • Coffee shop queuepush, pop, shift, unshift (mutation methods)
  • 🎵 Music playlistsort, reverse, find, at (ordering & navigation)
  • 📚 Student gradesevery, some, includes, flat (checking & searching)
  • 🛵 Food delivery orderssplice, slice, indexOf, concat (slicing & merging)

What's inside each module

Every module has three parts:

  1. Playground — Pick a scenario, watch it animate, and experiment with the live code
  2. Reference — All methods grouped by what they do (mutates, returns new array, iterative, search)
  3. Real examples — Code written the way you'd write it on an actual project

What's coming next

The Array module is live now. Here's the roadmap I'm building toward:

  • String Methods (32 methods — form validation, parsing, URL building)
  • Promises & Async/Await (with animated API call simulations)
  • DOM Manipulation (with a live mini-page preview)
  • Map & Set
  • Object Methods
  • Regex, Destructuring, Closures, Prototype, Web APIs...

One module at a time, built properly.


It's open source — contributions welcome

The whole thing is pure HTML, CSS, and JS. No build step. GitHub Pages auto-deploys from main.

Adding a new module is intentionally simple:

# 1. Fork and clone
git clone https://github.com/mankal-27/Fork-My-Brain

# 2. Copy the template
cp -r js-array-guide js-string-guide

# 3. Replace the scenario data in js/scenarios.js
# 4. Add a card on the homepage
# 5. Push — it deploys automatically
git push
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If you've ever thought "I wish there was a better way to learn X method" — this is the place to add it.


Try it

🔗 Site: mankal-27.github.io/Fork-My-Brain

GitHub: github.com/mankal-27/Fork-My-Brain

Would love feedback — what JS topic would you want to see covered next? Drop it in the comments.

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