JavaScript

Join the JavaScript Track
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

119 Mentors

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

57,182 Students

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

103 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 Steven Atkinson

Steven Atkinson https://github.com/mrstebo

Javascript is one of the greatest languages to get your teeth stuck into. I'll be on hand to help guide anyone on a quest to tame the JS beast!
Avatar of Nick Bespaliuk

Nick Bespaliuk https://github.com/ukolka

I have used JavaScript professionally. Exercism helped me gain new insight so I'm giving back.
Avatar of Derk-Jan Karrenbeld

Derk-Jan Karrenbeld https://github.com/SleeplessByte

JavaScript has been part of my day-to-day job for over 7 years -- A love-hate relationship
Avatar of Eliza Marcum

Eliza Marcum https://github.com/elizabrock

I'm a software engineer, educator and perpetual optimist. I've been programming in Ruby professionally for over 10 years, and taught Ruby/Rails for 4 of those years.
Avatar of Thomas Gamble

Thomas Gamble https://github.com/gambtho

Enjoy solving problems and helping others learn. I've written javascript professionally, and also use it for open source projects.
Avatar of Debasish Sahoo

Debasish Sahoo debck

Love writing Javascript for Backend applications and open-source development.
Fun. Challenging. Interesting

Community-sourced JavaScript exercises

These are a few of the 103 exercises on the JavaScript track. You can see all the exercises here.

Grade School
medium
arrays
maps
sorting
House
medium
arrays
recursion
strings
conditionals
loops
Alphametics
medium
algorithms
games
Hamming
easy
equality
strings
conditionals
loops
Protein Translation
easy
algorithms
strings
conditionals
loops
Allergies
medium
arrays
bitwise operations
conditionals
loops
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 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.
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