30 Free Resources To Help You Learn JavaScript Fundamentals

JavaScript is an incredibly powerful and complex language that can take years to fully master. When you‘re just starting out, it‘s easy to get distracted by flashy frameworks and libraries and skip over the fundamentals. However, taking the time to deeply learn and understand the core concepts of JavaScript will make you a much stronger developer in the long run.

Trying to build applications without a solid grasp of the fundamentals is like trying to run before you can walk. You might make some progress, but you‘ll quickly get tripped up and frustrated when things break and you don‘t know how to fix them. On the other hand, by mastering the fundamentals, your code will be more bug-free, you‘ll be able to solve complex problems more easily, and learning new frameworks will be a breeze since you‘ll understand how they work under the hood.

So what are the key JavaScript fundamentals that beginners should focus on? Here are the most important concepts, along with some of the best free resources for learning each one:

Variables and Scoping

Variables are the building blocks that allow us to store and work with data in our programs. Scoping refers to where variables can be accessed. Properly using variables and understanding scope is crucial for writing clean, maintainable code.

Resources:

• JavaScript.info: Variables – Comprehensive guide on variables, scope, hoisting, and more
• WebDevSimplified: var vs let vs const – 6-minute video explaining the differences between the three ways to declare variables
• Scotch.io: Declaring Variables – Interactive tutorial on variables and scope

Data Types

JavaScript has 7 basic data types that you‘ll work with all the time: number, string, boolean, null, undefined, object, and symbol. Having a solid understanding of the different types and how to use them is a fundamental skill.

Resources:

• Educative.io: Types & Coercion – Interactive course diving deep into JS data types and type coercion
• JavaScript.info: Data Types – Overview of the different data types with examples and explanations
• Udacity: Intro to JavaScript – Free video course. Lesson 1 covers data types in depth

Arrays and Objects

Arrays and objects are the workhorses of JavaScript. Almost every program you write will use them to store and work with collections of data. Mastering the many ways to manipulate arrays and objects is a must.

Resources:

• FreeCodeCamp: The Definitive JavaScript Handbook – Handbook with sections on array and object methods. Tons of helpful code examples!
• Traversy Media: 20 JavaScript Array & Object Methods – 20-minute crash course video covering the most useful methods
• Eloquent JavaScript – Free online book. Chapter 4 provides and in-depth look at arrays, objects, and data structures

Functions, Callbacks, and Scope

Functions are the heart of JavaScript. Understanding how to define and call functions, pass arguments, use callbacks and closures, and leverage scope is key to being an effective JS programmer.

Resources:

• MDN: Functions – Comprehensive guide on defining and calling functions, scope, closures, and more
• JSConf: What the heck is the event loop anyway? – Legendary talk explaining callbacks, asynchronous code, and the event loop
• FreeCodeCamp: The Beginner‘s Guide to JavaScript Functions – Covers all the fundamentals of using functions with tons of code examples

DOM Manipulation

JavaScript is most often used to create interactive web experiences by manipulating elements on a page. Having a strong grasp of how to use JavaScript to interact with the DOM is crucial for any web developer.

Resources:

• DigitalOcean: Intro to the DOM – In-depth tutorial covering what the DOM is, how it‘s structured, and how to access and update elements with JS
• JavaScript.info: Browser – Document, Events, Interfaces – Comprehensive set of chapters on working with the DOM. Covers beginner to advanced topics
• How to Manage HTML DOM with JavaScript – Interactive tutorial with hands-on examples of DOM manipulation

ES6+ Syntax

In 2015, the ECMAScript specification for JavaScript had a huge update with the release of ES6. Even if you‘re just starting to learn JS, it‘s important to learn the newer syntax and features like arrow functions, classes, promises, async/await, and more.

Resources:

• Scrimba: Intro to ES6+ – Free 1-hour video course covering all the key ES6 syntax and features. Hands-on coding in the browser
• Exploring JS: Core ES6 Features – Overview of the most important ES6 additions with code examples
• The ES6 Cheat Sheet – Cheat sheet with tons of example code for all the main ES6 features

Putting it All Together

The best way to cement your understanding of the fundamentals is by using them to build real projects from scratch. Pairing the conceptual knowledge with hands-on experience is the ultimate way to grow and improve as a developer.

Here are some of my favorite resources for project-based learning:

• JavaScript30 – 30 fun projects to build in 30 days using plain JavaScript. Excellent way to practice the fundamentals
• How to Build Real-World Applications with Vanilla JavaScript – In-depth article walking through 4 practical vanilla JS projects
• Modern JavaScript from the Beginning – Free Udemy course focused on building real projects with plain JavaScript

Learning and mastering the JavaScript fundamentals takes time and consistent practice. Don‘t get discouraged if it feels overwhelming at times – every expert developer started as a beginner. If you dedicate yourself to solidifying your core JS skills, you‘ll have an incredibly strong foundation to build on for years to come.

So what are you waiting for? Bookmark this list of resources and start (or continue) your journey to JavaScript mastery today. Happy coding!