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.
Join the JavaScript Track
Track mentors

152 Mentors

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

100,218 Students

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

107 Exercises

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

About JavaScript

export function hello() {
  return 'Hello, World!';
};

ECMAScript is the standard that defines JavaScript, a programming language that allows web pages to be dynamic. It is an interpreted language, which means that it doesn't need to be compiled: instead the interpreter (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*!

JavaScript is not only for use in the browser. JavaScript runtimes, such as NodeJS and deno allow you to write, launch and serve requests on webservers. Other frameworks, such as Electron use JavaScript to write cross platform applications for Windows, Linux and Mac OS. Mobile app development is also a possibility, utilising react-native, ionic and various others, with expo now allowing to target Android, iOS and the web, all at once.

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.

But because new syntax and features are coming to JavaScript each year, support for these changes is often incomplete in current browsers and the latest node. This doesn't mean we can't use it. Tools such as Babel offer transpilation for most features, allowing us to write as if it's the future.

Note: This track supports the latest ECMAScript syntax via Babel and the @babel/preset-env plugin, and new experimental features are enabled with each update of that plugin, matching the release of the specifications. It automatically adapts to your local node installation. This means you don't need to worry about what is and isn't supported.


* There is a small number of browsers that doesn't ship with a JavaScript runtime, or that has disabled JavaScript execution by default.

Join the JavaScript track

Exercism is a great website

Exercism is a great website where I was able to have some very interesting challenges.

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 Michael Dimmitt

Michael Dimmitt My Profile Page

Passionate about user experience helping others, I write a lot of javascript and am always learning new things.
Avatar of Julia Gao

Julia Gao http://ryoia.github.io

I am a front-end developer who has been using vanilla JavaScript for the past three years. I would love to help others on this track.
Avatar of Constantine Akritides

Constantine Akritides https://github.com/CodeZeus-dev

I am a Makers Academy student in London and a Junior Software Engineer, currently coding in Javascript, Ruby, and C#. I am willing to help and mentor my fellow devs and I usually follow a TDD/BDD approach.
Avatar of Jonathan Hawley-Peters

Jonathan Hawley-Peters https://github.com/jonathanhawleypeters

For over a decade I've programmed as a hobby. In 2016 I started working as a web developer and receiving mentorship was a big part of what made that change possible. To me, mentoring people who are learning Javascript feels like a natural part of the progression and often brings me joy.
Avatar of Pascal Spiesz

Pascal Spiesz GitHub

I'm a JavaScript developer and I think that mentoring is a great way to improve knowledge for the mentor and the mentees.
Avatar of Brandon A Welsh

Brandon A Welsh https://github.com/BrandonArmand

Javascript is the first line of defense! Reach out to me and get in touch with any questions or collaborations, I love to network and help.
Fun. Challenging. Interesting

Community-sourced JavaScript exercises

These are a few of the 107 exercises on the JavaScript track. You can see all the exercises here.

Rational Numbers
medium
algorithms
floating point numbers
math
Robot Name
medium
exception handling
randomness
regular expressions
sets
conditionals
Allergies
medium
arrays
bitwise operations
conditionals
loops
Two Fer
easy
optional values
strings
text formatting
Reverse String
easy
loops
strings
Resistor Color
easy
arrays
strings
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 Evelyn Stender

Evelyn Stender Website

Full-stack developer passionate about Javascript. Studying Go on my free time.
Avatar of Tejas Bubane

Tejas Bubane My blog

Primarily a Ruby & Javascript coder, getting better at functional programming, emacs lover.
Avatar of Josh Goebel

Josh Goebel Blog: Running Blind

I mostly write Ruby & JavaScript (for fun and profit) but I dabble with TypeScript, Elixir, Nim, Arduino, and such.
Avatar of Kristina Born

Kristina Born

Full-stack developer and lover of all things linguistic. Teaching is the best way to learn.
Avatar of Derk-Jan Karrenbeld

Derk-Jan Karrenbeld My website

All-round programmer, manager and owner of a Dutch software agency specializing in bespoke and tailored code.

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Join the JavaScript Track