Fabian Frank Werner

Posted on Aug 7

How to ACTUALLY learn JavaScript... A roadmap for beginners

#webdev #javascript #beginners #learning

An excellent salary, back problems, and social isolation…

If that sounds good to you, I recommend learning the JavaScript programming language.

Learning to code was the best investment in my life.

And it cost me approximately $0, thanks to all the free resources available on the internet.

But how does one learn JavaScript as a complete beginner?

Luckily, you don’t need to be very smart, but you do need to work very hard. And put in the hours required to learn JavaScript as a usable skill.

But hours doing what exactly? Where do I even start?

Sadly, there is no guaranteed step-by-step program, but luckily, there is this post giving you a beginner roadmap to learn JavaScript step by step.

I’m going to blitz through the key JavaScript topics…

Giving you a big‑picture overview and the right order to tackle them later in your own self‑guided deep dive.

What is JavaScript?

JavaScript is the language that powers everything from flashy websites to full‑blown server apps, and occasionally, your late‑night debugging-induced existential crisis. It’s the only programming language that works in every browser, meaning if you’ve clicked, scrolled, or been annoyed by a pop‑up, you’ve met JavaScript.

A Brief (and Weird) History of JavaScript

JavaScript has been through more name changes than a wannabe pop star. It started as Mocha, then got rebranded to LiveScript, before Netscape slapped on “JavaScript” to ride the hype wave of Java… which is ironic, because JavaScript and Java have about as much in common as hamsters and ham radios.

How to Run JavaScript

Want to run JavaScript? Easy. Stick it in a <script> tag in your HTML, type it straight into the browser console, or—if you like your code without a browser babysitter—fire it up in Node.js. There are fancier ways, but this will get you from “I have code” to “look, it runs!” in seconds.

Scopes (a.k.a. Where Your Variables Live and Die)

Variables are just boxes for storing values, and in JavaScript, where you declare them determines who can see them. There’s global scope (everyone can see it), local scope (only certain parts can), function scope, and block scope. Before 2015, we only had var, which was… fine, but also cursed. Then let and const showed up, giving us sane block scoping and making var the VHS tape of JavaScript—still playable, but why would you?

Datatypes

JavaScript has seven primitive datatypes—Number, BigInt, String, Boolean, Null, Undefined, and Symbol. Everything else? Objects. Arrays? Objects. Functions? Objects. Your hopes and dreams? …Still objects. You can check a variable’s type with typeof, but beware: typeof null says “object” because JavaScript likes to keep some of its weird 1995 quirks alive.

Implicit Type Casting (a.k.a. “JavaScript Will Guess for You”)

JavaScript loves to “help” by converting types behind your back. Sometimes it’s convenient, sometimes it’s a horror show. 1 + '1'? That’s '11'. 1 - '1'? That’s 0. Why? Don’t ask. This is one reason TypeScript exists: to stop JavaScript from playing guessing games with your data.

Keyed Collections

Beyond plain objects, JavaScript has Map, WeakMap, Set, and WeakSet. Maps let you store key/value pairs with any type of key. Sets are just unique collections of values. The “weak” versions? They don’t prevent garbage collection, so they’re good for memory‑sensitive data you don’t want hanging around forever.

JSON

JSON — Not a person. Not a typo. It stands for JavaScript Object Notation and is a lightweight data format for sending info between computers. It’s just strings that look like objects, and it’s everywhere: APIs, configs, and anything that needs to speak “structured text.”

Value Comparison Operators

JavaScript gives you == (equality) and === (strict equality). == will happily convert types before comparing, which can lead to “fun” surprises. === does a strict check for both value and type—generally the safer choice. Then there’s Object.is(), which is even stricter, because of course, we needed three ways to compare values.

Loops and Iterations

If you need to repeat something, you’ve got for, while, do...while, for...in, for...of, plus break to stop early and continue to skip steps. If your brain doesn’t hurt after learning them all, congratulations—you’re ready to write JavaScript that confuses future you.

Conditional Statements

If you need your code to make decisions, you’ll use if, if...else, or switch. The first two are straightforward. switch is for when you have multiple cases to check and want your code to look like a retro telephone switchboard.

Try, Catch, Finally

When things break—and they will—wrap your code in try to run it, catch to handle errors, and finally for code that runs no matter what. Perfect for cleanup, logging, or making sarcastic comments after everything explodes.

Utilizing Error Objects

When JavaScript throws an error, it hands you an Error object. You can inspect it to figure out what went wrong, then decide whether to fix it, log it, or just pretend it never happened.

Expressions and Operators

Everything from + (plus) to === (strict equality) to ?? (these things) fall under expressions and operators. There are a lot of them: arithmetic, logical, assignment, comparison, bitwise… and a few that only show up to ruin your day if you forget how they work.

Functions

Functions are reusable chunks of code you can call whenever you want. They take optional parameters, return optional values, and sometimes cause non-optional headaches.

Arrow Functions

The arrow function is the hipster version of functions—shorter syntax, no own this binding, and looks cooler.

IIFE (Immediately Invoked Function Expression)

IIFEs are functions that run as soon as you define them. This is great for quick, one‑off code execution.

Recursion

Recursion is when a function calls itself until it hits a “base case” and stops. Use it for elegant problem solving… or infinite loops if you mess it up.

Closures

A closure is when a function remembers the variables from the place it was created, even after that place is gone. It’s like a function with a secret backpack of data.

Built‑in Functions

Stuff like parseInt(), setTimeout(), and Math.random()—plus methods on Array, String, and Date—are ready to use without writing them yourself.

DOM APIs

JavaScript can poke, prod, and completely rearrange your web page via the DOM. Change text, update styles, remove elements, add elements—it’s all fair game.

The `this` Keyword

this changes depending on how and where you use it. Sometimes it’s the object you’re in, sometimes it’s the global object, and sometimes it’s undefined—because JavaScript loves to keep you guessing.

Asynchronous JavaScript

Some tasks—like fetching data or using a camera—take time, so JavaScript handles them asynchronously. That means your code can keep running while it waits for results.

Callbacks, Callback Hell, and Async/Await

Callbacks are functions passed into other functions. Too many nested callbacks turn your code into “callback hell”—a pyramid of doom. Async/await fixes that by making asynchronous code look synchronous, which your future self will thank you for.

Fetch

fetch() lets you grab data from servers and APIs. It returns a promise, which you can await like the cool kids.

Modules

Split your code into separate files, export what you need, and import it where you need it. Modules keep things organized and your sanity intact.

Chrome DevTools & Debugging

Every browser has dev tools for inspecting HTML & CSS, running JS in the console, setting breakpoints, and checking performance. Chrome’s Lighthouse can even rate your website—though be prepared for a brutal honesty session.

Now it’s your turn: pick a project, start building, break things, fix them, and repeat until you accidentally become a JavaScript developer.