How to Learn JavaScript - The Ultimate Guide
Everything you need to learn JavaScript online, including the basics of JavaScript, a list of online courses, JavaScript tutorials, projects, and much more.
Feb 24, 2023 • 3 Minute Read
By Dr. Kate Blake & Eduardo Freitas
Welcome and congratulations on your JavaScript learning journey! JavaScript is an incredibly versatile language that will not only let you make dynamic websites, but will open up a whole new world of web development for you.
Standard introductions to JavaScript focus on the HTML/CSS/JS triumvirate. That information is certainly useful; however, this guide is unique because it explains what JavaScript frameworks are (such as Node.js and React), why you should use them, and how to pick one. Understanding JS frameworks is the first step toward a real-world career in JS development.
We begin with basic JavaScript concepts, and then move into frameworks, a course catalog, and hands-on tutorials. We also point you toward more advanced JavaScript guides and information about what kind of jobs you can get with JS. Thank you for choosing Pluralsight to help you master JavaScript!
Learn JavaScript in 7 Steps
Should you learn JavaScript?
The process of learning a new programming language can be intimidating, so we are responding to some of the most common queries to put your mind at ease about the process.
What is JavaScript?
JavaScript is a scripting language for building websites and web applications. It's so commonly found on websites today that it's often called the "programming language of the web." JavaScript works alongside two other languages, HTML and CSS, to create dynamic web pages and interactive experiences.
JavaScript was created by Brendan Eich in just ten days in May of 1995 while working at Netscape Communications Corporation. It was originally called Mocha and was used to add interactivity to the client side of web pages.
JavaScript quickly gained popularity and was later standardized in the ECMAScript language specification. Today, it is used not only for client-side web development but also on the server side through Node.js and for creating desktop and mobile apps.
What is JavaScript used for?
JavaScript is used to make websites and web applications for desktop, tablet, and mobile devices. JavaScript allows for features like continual updates, animations, multimedia, interactive elements, and even game development. Essentially, it's the part of a web page's code that makes it come alive.
JavaScript features include contact forms, shopping carts, games, browser extensions, video and audio playback, and more.
Is JavaScript hard to learn?
JavaScript can be challenging, but it’s a fantastic language for beginners and self-directed learners! JavaScript shares a straightforward syntax with well-known programming languages like C and Java and, to a lesser extent, with Python. It also has a sizable community that supports language learning by offering materials and lessons.
But, like learning any programming language, mastering JavaScript takes time and effort. Knowing JavaScript could take more work if a learner has no prior expertise with programming. It can take a few months to really feel comfortable in the language, especially without prior programming experience.
What is HTML/CSS?
HTML and CSS are programming languages that play leading roles in website development. Hypertext Markup Language, also known as HTML, provides the webpage's structure and can be used to create static pages.
CSS, which stands for Cascading Style Sheets, controls a webpage's style or multiple pages on a site at once. Essentially, HTML provides the core functionality for the page, CSS is used for design elements, and JavaScript enables interactivity and animation.
Should I learn HTML/CSS first?
This is a complex topic, so let's lay out some facts. If you're going to develop websites, then at some point, you'll need to learn all three languages – HTML, CSS, and JavaScript. However, you don't have to know HTML or CSS to get started with JavaScript.
Some programmers recommend that you learn HTML and CSS first because they are essential. But others point out that JavaScript is generally an excellent introduction to programming for beginners. Here's a great article from Northcoders about why learning JS first is a good strategy for many coders.
It's also easy to work around HTML and CSS when you first set out. For instance, you can find ready-made HTML and CSS code to launch your first website project. Pluralsight's web-dev-starter code on GitHub is a free boilerplate that provides all the HTML you need to start coding in JS. You copy and paste these lines into your code editor. Also, through frameworks like Node.js, it's possible to run JavaScript without HTML.
What is a JavaScript framework?
A JavaScript framework is a pre-written library that provides a structure for JavaScript code and abstracts away routine chores to simplify the development of online applications. It offers a collection of templates and tools for building dynamic websites. Frameworks make it possible to build front end and back end infrastructure using JavaScript.
React, Angular, Vue.js, Next.js, and Node.js are the most well-liked and in-demand JavaScript client-side frameworks in 2023. React is categorized as a JavaScript framework even though it is a library.
What is the difference between a JavaScript library and framework?
In coding, as in life, libraries are repositories for resources. But instead of books, programming libraries contain collections of code snippets for specific tasks. This saves the coder from having to repeat the same language over and over again or creating complex functions from scratch. Examples of popular libraries include jQuery and React.js.
Similar to libraries, frameworks make it simpler for developers to tackle particular and challenging problems. While libraries and frameworks accomplish the same thing, the former tend to exercise greater control over the latter. Frameworks offer the fundamental structure and functionality of a program.
What is React?
React is a popular JavaScript library developed and maintained by Facebook. It uses a virtual DOM to update the UI efficiently and offers a declarative approach to programming. It also has a vast community and many available libraries and tools.
React's most notable feature is that it allows you to write HTML using JavaScript (rather than writing your JS into HTML as it was initially). As you're about to learn, several popular frameworks are built from React. Check out this piece – React, GraphQL, and Relay: A brief introduction – for a deeper dive into React.
Basic features of React
- Components: JavaScript classes or functions that represent reusable UI elements.
- JSX: A JavaScript syntactic extension used in React to describe UI elements
- Props: Information that a component receives from its parent component.
- State: An updated data format for managing component state.
- React can update the actual DOM effectively thanks to the virtual DOM, an in-memory specification of a UI tree.
- ComponentWillUnmount and componentDidMount are examples of lifecycle methods that are called upon at certain times throughout a component's lifecycle.
- Event Handling: To manage user interactions with components, React uses event handlers.
- Render elements are conditionally dependent on the state of the component.
Below is an example of React code:
class MyComponent extends React.Component {
state = { count: 0 };
handleClick = () => {
this.setState({
count: this.state.count + 1
});
};
render() {
return (
<div>
<p>Count: {this.state.count}</p>
<button onClick={this.handleClick}>Increase</button>
</div>
);
}
}
Advantages of React
- Reusable components: Promotes modular development and makes it simple to reuse parts and share code between projects.
- The virtual DOM enhances application speed by effectively updating only the changed portions of the user interface.
- Strong Community: React has a sizable and vibrant developer community where you may receive assistance, guidance, and a wealth of information.
- Popularity: If you're looking for dependable and well-supported technology, React is an excellent option. Numerous companies, including Facebook, Airbnb, Netflix, and more, utilize it extensively.
Disadvantages of React
- Even while React is very easy, larger applications created with it can be challenging to maintain and grow in complexity.
- React has a steep learning curve, but understanding it can take some time, even for professionals with experience in JavaScript or web development.
- Over-reliance on JavaScript: JavaScript is a critical component of React. This can be a disadvantage for some developers, who prefer to build most of their application logic in a more conventional back-end language.
- Performance Overhead: React's use of a virtual DOM and frequent updates to the actual DOM can impact performance, particularly in more significant apps.
Ultimately, the decision to use React or not should be based on the specific needs of your project and your preferences as a developer.
What is Angular?
Angular is a framework for building scalable web applications. Developed initially as AngularJS, the current Angular framework is now built on TypeScript, which we'll cover more about below. Angular has robust libraries and developer tools for building, testing, and debugging.
Many significant companies have widely adopted Angular, an open-source Google product. A wide-range of well-known web services depend on Angular for front-end development, such as Gmail, PayPal, Weather.com, etc.
Basic features of Angular
Angular uses modules to divide an application into smaller parts, each with its components and services.
- Components represent the basic Angular application's blocks, consisting of a template, class, and metadata.
- When a component's class and template communicate, you can display component data and react to user events. This is known as data binding.
- Directives in Angular Modify the behavior and appearance of an element within a template by repeating components or adding styles to particular features.
- On the other hand, services are reusable logic, such as data access or error handling, that can be shared between components.
- Beyond that, Angular also relies on Dependency injection by inputting dependencies into a component or service to increase the code's modularity.
Below is an example of an Angular component displaying a message:
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
template: `
<h1>{{message}}</h1>
`,
styles: [`
h1 {
color: blue;
}
`]
})
export class AppComponent {
message = 'Hello, Angular!';
}
In this example, @Component is a decorator that provides metadata for the component, such as its selector and template.
The template property defines the HTML structure of the component, and the message property is a data property displayed in the template using binding.
The styles property defines styles specific to the component. The component class, AppComponent, is exported so it can be used in different parts of the application.
The Bottom Line
Use Angular if you require high-performing, scalable, complicated online applications, typically in a commercial setting.
Still curious about Angular? Check out these posts:
What is Next.js?
Next.js is a framework built on React for creating web applications. It's designed to improve the developer experience as well as the functionality and interactivity of the application. It aids in everyday tasks such as routing, data fetching, and integration while making it easier to create faster applications with improved user experience.
One everyday use of Next.js is developing Jamstack websites. Jamstack is an approach to building websites optimized for digital business objectives.
Jamstack allows developers to create features like modular web applications and prerendered webpages. Essentially, pages constructed this way have many benefits of static pages, such as speed, but still contain dynamic elements.
Basic features of Next.js
- Next.js is built for server-side rendering (SSR), which enhances performance and SEO by automatically creating HTML for each page on the server and sending it to the browser.
- It also uses file-based routing, so every file in the page's directory corresponds to a route in the application.
- Next.js also uses dynamic import, which enables code splitting, enabling lazy loading of specific program components to enhance efficiency.
Below is an example of a Next.js page that displays a message:
import React from 'react';
export default function Home() {
return (
<div>
<h1>Hello, Next.js!</h1>
</div>
);
}
In this example, the Home component is defined as a default export, which can be easily imported into other application parts. The component returns a simple HTML structure using JSX, transpiled to JavaScript by Next.js.
The Home component can be accessed at the / route of the application since it is placed in the pages directory and named index.js.
The Bottom Line
You may want to choose Next.js if you're running a business website and need fast web pages and UX and SEO friendly, but you don't necessarily want to rebuild the whole website.
What is Vue.js?
Vue.js, referred to as Vue (pronounced as view), is an open-source JavaScript framework for writing UIs that focuses on the view layer and can be easily integrated with other libraries or existing projects. It is a simple and versatile framework.
Vue was created by Evan You after working for Google and using Angular on different projects. Evan's goal was to use the parts of Angular that he enjoyed and build something easy to use, lightweight, and still has many of the significant aspects and features of Angular.
Vue uses an HTML-based template syntax that enables reactive data binding to the DOM and extends HTML elements as reusable components. Vue provides front-end support hashed routing through the Vue Router package.
Vue is also a progressive framework, which means that if you already have an existing web application, you can hook Vue into one of its parts—which might need a dynamic and more interactive user experience. Vue has excellent performance characteristics.
Basic features of Vue
- A template, script, and styling are examples of reusable application-building parts known as components. Templates use HTML-based syntax to define a component's structure.
- Vue allows you to display component data and respond to user actions by using data binding, which enables communication between a component's script and template.
- Directives alter the behavior and appearance of a template element, for instance, by conditionally displaying elements or binding styles.
- Methods with reusable functionality that may handle user events or conduct API queries are used by components.
- To increase efficiency, computed properties allow users to alter the value of a property based on other characteristics.
- Watchers monitor changes to a property and react with unique logic.
- Mixins are used for providing shared logic or styles, which are reusable sets of component options that may be mixed into other components.
- Navigation within an application and between various components and routes is managed by routing.
Below is an example of Vue.js code:
<template>
<div>
{{ message }}
</div>
</template>
<script>
export default {
data () {
return {
message: 'Hello Vue.js!'
}
}
}
</script>
In this example, the message "Hello Vue.js!" is displayed in a div element. The message is stored in the component's data and is dynamically rendered using the double curly brace syntax {{ }}.
The Bottom Line
Vue allows applications to scale quickly by supporting reusable components out-of-the-box, each with its HTML, CSS, and JavaScript—this means that an application can be split into smaller functional parts, which can be later reused.
What is Node.js?
Node.js is an open-source, cross-platform JavaScript runtime environment that executes JavaScript code outside a web browser. It allows building server-side applications with JavaScript.
Node.js is the most generally used server-side runtime, and Express.js is the most widely used server-side framework; both are frequently combined. JavaScript was initially designed for "client-side scripting," meaning that the code runs on the user's computer, usually their browser.
The Node.js website describes Node as an "asynchronous event-driven JavaScript runtime," but what does that mean? Let's break it down:
Event-driven: the program operates based on input from the user. For example, when you are asked to click a box, that's an event, and the code that follows as a result of your click is event-driven.
Asynchronous: the program can handle multiple events at once.
JS runtime: it does these things while the program is running in JS
The definition doesn't express how versatile Node is, though. There's a reason companies like Twitter, Spotify, Reddit, and LinkedIn, among many others, have turned to Node for their server-side JS needs. Its various applications include real-time chats, data streaming, dashboards, and queued inputs.
Basic features of Node.js
A popular choice when working with Node.js is to use the Express.js framework. You must install Express by running the npm install express command to do that.
To create an Express app, start by requiring the express module and creating an instance of the express application:
const express = require('express');
const app = express();
To handle HTTP requests, you can use the app.get() or app.post() methods to define endpoints and specify what should happen when requests are made. For example:
app.get('/', (req, res) => {
res.send('Hello World!');
});
Here's how to use Express to serve static files such as images, CSS, and JavaScript files.static() middleware:
app.use(express.static('public'));
To handle form data submitted in a request, you can use the body-parser middleware:
const bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({ extended: true }));
By using a template engine, such as Pug or EJS, you can set it as the view engine using app.set():
app.set('view engine', 'pug');
To render views, you can use the res.render() method and pass in the name of the view and any data that should be used to generate the view:
app.get('/', (req, res) => {
res.render('index', { title: 'My App' });
});
To start the Express server, use the app.listen() method and pass in a port number:
app.listen(3000, () => {
console.log('Express app listening on port 3000!');
});
To learn more, check out these posts from our blog:
jQuery: A JavaScript Library
JQuery is not a framework, but it’s such a popular library for building websites that we felt it deserved some attention. Its primary goal is to help developers do more while writing less code, and it makes working with things like HTML documentation, events, animations, and Ajax much easier.
Everyday tasks you can perform with jQuery
- Document ready: $(document).ready(function(){ ... });
- Selectors: $(el), $('#id'), $('.class'), $('element')
- Attribute Selector: $('[attribute=value]')
- Accessing a child element: $(el).children()
- Accessing a parent element: $(el).parent()
- Accessing a sibling element: $(el).siblings()
- Finding an element: $(el).find('element')
- Get CSS: $(el).css('property')
- Set CSS: $(el).css('property', 'value')
- Add a class: $(el).addClass('class')
- Remove a class: $(el).removeClass('class')
- Toggle a class: $(el).toggleClass('class')
- Hide an element: $(el).hide()
- Show an element: $(el).show()
- Toggle an element: $(el).toggle()
- Fading in an element: $(el).fadeIn()
- Fading out an element: $(el).fadeOut()
- Fading a toggle: $(el).fadeToggle()
- Sliding down an element: $(el).slideDown()
- Sliding up an element: $(el).slideUp()
- Sliding a toggle: $(el).slideToggle()
- Clicking an element: $(el).click(function(){ ... });
- Mouse entering an element: $(el).mouseenter(function(){ ... });
- Mouse leaving an element: $(el).mouseleave(function(){ ... });
- Hovering an element: $(el).hover(function(){ ... });
If you're considering building a website, you'll want to learn more about jQuery.
Selecting a JavaScript framework
At the end of the day, your choice of framework should reflect what kind of work you want to do and how you want to prepare yourself for the job market. That’s why we selected popular frameworks that you are likely to see on job solicitations.
In addition to how you want to position yourself as a developer, some other factors to consider when choosing a framework include
Your background or your development team’s background, qualifications, and existing frameworks.
How important is performance? Some frameworks perform better than others.
A large community with lots of resources, guides, and third-party libraries can improve the experience of learning and using a framework.
Looking at the roadmaps for the frameworks you're thinking about is crucial because some frameworks can have a more secure future than others.
What is TypeScript?
TypeScript is the next stage in JavaScript evolution. It's an object-oriented programming language built on JavaScript that adds greater functionality and ease of use to the original language. TypeScript provides the syntax for "types," which is an easier way to refer to the properties and functions associated with a value. TypeScript converts to JavaScript, meaning it can run anywhere you use JS.
TypeScript is quickly replacing JavaScript as the number one language for programmers primarily because it improves the developer experience. Its syntax is more straightforward and makes it easier for programmers to avoid errors; it offers more scalability for development teams; and makes debugging more manageable. In short, it can be used interchangeably with JavaScript simultaneously as it resolves common problems with JS.
Examples of TypeScript
// Declare variables
let variableName: dataType = value;
// Basic types
let num: number = 42;
let bool: boolean = true;
let str: string = "Hello, World!";
// Declare arrays
let arr: number[] = [1, 2, 3];
let arr: Array<number> = [1, 2, 3];
// Declare tuples
let tuple: [string, number] = ["Hello", 42];
// Declare enum
enum Color {Red, Green, Blue};
let c: Color = Color.Green;
// Unions
let variableName: string | number = "Hello";
// Functions
function add(a: number, b: number): number {
return a + b;
}
// Declare an interface
interface Person {
firstName: string;
lastName: string;
}
let p: Person = {firstName: "John", lastName: "Doe"};
// Declare a class
class Student {
fullName: string;
constructor(public firstName: string, public lastName: string) {
this.fullName = firstName + " " + lastName;
}
}
let s = new Student("John", "Doe");
What do I need to download to get started with JavaScript?
Pluralsight's JavaScript: Getting Started course will walk you through what you need to begin your JS journey. At the very least, you will need a code editor. A code editor provides an environment for you to create scripts. A few popular ones include
In addition, if they're not already installed on your computer, you probably want to download Git and Node.js. For a full guide to installing these components, visit "Installing Development Software" when you're signed into Pluralsight.
If you’re going to work with one of the frameworks described in this guide, you may need to install additional packages:
For Vue, install Node.js first and then check out this Vue quick start guide
Angular also requires Node.js, and the Angular CLI is installed via Node Package Manager (NPM)
Are you ready to learn JavaScript?
Pluralsight has a massive catalog of over 140 JavaScript courses, from absolute beginners to seasoned experts. Our resources include video lectures, tutorials, and hands-on learning projects. Here are just a few of our online course offerings.
JavaScript Courses for Beginners & Beyond
We recommend launching your JavaScript education with Pluralsight's JavaScript Core Language learning path. This path comprises ten courses to help jumpstart your coding adventure. You can also check some of our beginner courses:
Courses on JavaScript Frameworks and more
For those who want to get started with a specific framework or library. Browse our online courses for more.
React.js Courses
Node.js Courses
Working with Node.js (Path)
AngularJS Courses
Typescript Courses
Hands-On JavaScript Tutorials
Pluralsight's courses include exercises and code you can follow on your computer. There are also tons of free tutorials online for JavaScript learning and practice, and GitHub, a social platform for coders, has an extensive repository of JavaScript exercises.
Where can I practice JavaScript on Pluralsight?
If you're a hands-on learner, Pluralsight offers several interactive courses on beginner JavaScript topics:
When can I start my first JavaScript project?
You can start your first JavaScript project immediately when you begin a new course. For most people, your first JS code will be the "Hello World" project, which teaches you how to print a phrase on the screen. But for other beginners' tasks, try some of these from Pluralsight:
What can you do with advanced JavaScript skills?
JavaScript is one of the most demanded programming languages, and there’s lots of opportunities to work in web development with advanced JS skills.
Types of jobs for a JavaScript developer
Learning JavaScript helps prepare you for a career in software development and/or engineering. One reason we encourage you to start learning within a framework is that it enables you to work on both the back and front ends of a project. This opens up a lot of opportunities in the world of full-stack engineering.
Here are a few jobs for JavaScript developers including salary information from Indeed.com:
Software engineer: Average base salary of $114,168
Full-stack engineer: Average base salary of $119,828
Web developer: Average base salary of $79,307
Pick up some popular advanced JS guides
Knowing what other JavaScript developers are searching for online can be a great way to expand your JS knowledge, even as a beginner. It can give you a head start in identifying the more advanced and useful applications of the language. Here are a few of Pluralsight's most accessed guides on popular JavaScript topics:
The Map() Function
"The map() function lets you manipulate the items in an array by iterating and accessing individual items. This guide teaches you how to use and export the map() function."
Read more: How to Use the Map() Function to Export JavaScript in React
Convert Strings to JSON Objects
"String data can be easily converted to JSON using the stringify() function, and also it can be done using eval(), which accepts the JavaScript expression that you will learn about in this guide."
Read more: Convert Strings to JSON Objects in JavaScript with eval()
JavaScript TypeError: Cannot Read 'Then' of Undefined
"This guide will cover two code examples containing bugs that cause this TypeError and then refactor the code to resolve the issue."
Read more: Resolving the JavaScript Promise Error "TypeError: Cannot Read 'Then' of Undefined."
JavaScript with Ajax and Razor Partial Views
"Ajax helper methods and extensions in the System.Web.Mvc and System.Web.Mvc.Ajax namespaces can be combined with JavaScript and MVC partial views to create flexible, interactive web pages with minimal code. When using these resources, developers should know a few techniques necessary to create effective code."
Read more: ASP.NET MVC - Using JavaScript with Ajax and Razor Partial Views
Meet other developers
Please don't be shy when it comes to joining the programming community. Connecting with other developers can be a great way to find helpful problem-solving resources. Here are a few places where developers can meet each other:
Stack Overflow (great for finding help with programming problems)
Don't underestimate Twitter, Instagram, TikTok, or YouTube either. Influencers can be a fantastic source of inspiration and information.
Measure your JavaScript Skill IQ on Pluralsight
If you've done a little JS in the past, and want to know how your skills stack up against other programmers, try measuring your JavaScript Skill IQ. You'll get two tries if you don't like your first score. This feature is for Pluralsight subscribers, so consider starting a free trial if you want to access it.
Eduardo Freitas
Eduardo is a technology enthusiast, software architect and customer success advocate. He's designed enterprise .NT solutions that extract, validate and automate critical business processes such as Accounts Payable and Mailroom solutions for all types of organizations.
He's designed and supported production systems for global names such as Coca Cola, Enel, Pirelli, Fiat-Chrysler, Xerox and many others. He's a well-known specialist in the Enterprise Content Management market segment, specifically focusing on data capture & extraction and document process automation. He designed a supplier invoice processing system for Agfa that achieved 50% straight-through processing (50% of invoices extracted from paper, validated and exported into SAP without any human validation). He's also loves to write about cutting-edge technologies. He loves helping customers succeed. In his free time, he enjoys spending time with his family and being outdoors. He loves running and sports.
Eduardo is also a course author here on Pluralsight, and has written on topics like Python, automation, cloud computing, working with databases, and more.
Dr. Kate Blake
Dr. Kate Blake is a writer with a penchant for technical material, including computer programming and the history of science and technology. Though she has been coding since she was twelve, her professional background is in academia, and she recieved her PhD from Indiana University in English in 2017 and worked as an English Professor for several years while publishing research on a variety of topics,
Since leaving academia, she now works in technology education. She is currently employed at Pluralsight as an SEO analyst, where she's able to combine her love of programming languages with her background in writing and education.
