JavaScript

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JavaScript is a scripting language, primarily used for creating dynamic websites and programming web servers. It's a very popular language, and supports a variety of programming paradigms.
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Track mentors

71 Mentors

Our mentors are friendly, experienced JavaScript developers who will help teach you new techniques and tricks.
Track students

23,865 Students

Join thousands of students who have enjoyed learning and improving their skills by taking this track.
Track exercises

96 Exercises

Hundreds of hours have gone into making these exercises fun, useful, and challenging to help you enjoy learning.

About JavaScript

class HelloWorld {
  hello() {
    return 'Hello, World!';
  }
}

export default HelloWorld;

ECMAScript is the standard that defines JavaScript, the language that allows web pages to be dynamic. It is an interpreted language, which means that it doesn't need to be compiled by the programmer: instead the client (such as a web browser) will parse the code and turn it into code that their machine can run - suitable for creating dynamic websites that can run on any browser on any computer!

In addition to use in web pages with modern web browsers, and it can also be executed on servers where the NodeJS platform is installed where it can be used for creating a web server too.

"ECMAScript has grown to be one of the world’s most widely used general purpose programming languages. It is best known as the language embedded in web browsers but has also been widely adopted for server and embedded applications." —ECMA International Language Specification

Starting with the 6th edition (commonly known as ES2015 or ES6) in 2015, a new edition of the standard will be released each year. The 6th edition was a major update which brought many enhancements over ES5, including notably template strings, expressive arrow function syntax, and cleaner syntax for defining classes.

However, support in current browsers is incomplete, and often requires transpilation with a tool like Babel.

_Note: This track supports the latest ECMAScript syntax via Babel and the babel-preset-env plugin, and new experimental features will be enabled with each release of the specification. Here, you will find code that not all browsers are able to run.

Join the JavaScript track

Exercism is a great website

What I like about it is that I am able to solve the challenges in a TDD way working in a environment that I am familiar (my own PC not a browser IDE) and the cherry on the top of the cake is that I have access to code reviews.

Relaxed. Encouraging. Supportive.

Meet the JavaScript Track mentors

Once you join the JavaScript language track, you will receive support and feedback from our team of mentors. Here are the bios of a few of the mentors of this track.

Avatar of Edouard Souan

Edouard Souan

I write javascript and other languages professionally. I love to learn and share with others.
Avatar of Leonardo Cardoso

Leonardo Cardoso https://github.com/Leocardoso94

undefined is not a function
Avatar of Nada Ghanem

Nada Ghanem https://github.com/nadaa

A continous learner, love technology and nature.
Avatar of Michael Anderson

Michael Anderson https://github.com/usufruct

ECMAScript is the hobo of the internet. It is also the train I took into the world of software years ago.
Avatar of Volkan Erdogan

Volkan Erdogan https://github.com/volcain-io

I'm self-employed and doing web & mobile apps (ECMAScript/JavaScript) & I'm in love with all the possibilities you get with that language.
Avatar of Ian Fosbery

Ian Fosbery https://www.codeguy.io

I've been a programmer for over 15 years. My day-to-day lately has been JS everywhere. Everywhere. I've really gotten into functional programming in recent years, which is how I tend to write Javascript. But, it can be written in many different ways and it's all about the context.
Fun. Challenging. Interesting

Community-sourced JavaScript exercises

These are a few of the 96 exercises on the JavaScript track. You can see all the exercises here.

React
hard
algorithms
events
reactive programming
Variable Length Quantity
medium
bitwise operations
transforming
Nth Prime
medium
algorithms
control flow conditionals
control flow loops
exception handling
integers
math
RNA Transcription
easy
strings
transforming
Food Chain
medium
algorithms
text formatting
ETL
easy
control flow loops
integers
maps
transforming
Passionate. Knowledgeable. Creative.

Meet the JavaScript Track maintainers

The JavaScript Maintainers are the brains behind the JavaScript Track. They spend their spare time creating interesting and challenging exercises that we can all learn from. We are incredibly grateful for their hard work. Here are the bios of a few of the maintainers of this track.

Avatar of Rubén Chavarría

Rubén Chavarría Here is where I blog

I'm a Web Developer with a passion for taking code that is hard to maintain and cleaning, refactoring, and bringing it back into a manageable state
Avatar of Matt Morgan

Matt Morgan

Learn, teach, build, repeat!
Avatar of Tejas Bubane

Tejas Bubane My blog

Primarily a Ruby & Javascript coder, getting better at functional programming, emacs lover.

Get started with the JavaScript track. As with everything on Exercism, it's 100% free!

Join the JavaScript Track