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

95 Mentors

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

36,588 Students

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

99 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, 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 for the newest syntax is incomplete in current browsers and the latest node, 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 runtimes are able to run.

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Exercism is a great website

The reviews are incredibly helpful because they help me see things that I missed, learn about new ways and sometimes interesting discussions that can add a fun twist to maybe a simple problem.

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 Plotke

Michael Plotke michael.plotke.me

I'm paid to write JavaScript. I mostly enjoy it. I also enjoy teaching. Exercism is a nice convergence.
Avatar of CJ Ting

CJ Ting https://github.com/fate-lovely

To be honest, I don't like JS that much, but I've been writting it professionally for a long time. If you use it carefully, it's a wonderful language.
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 Daniel Couper

Daniel Couper https://github.com/DanCouper

I've programmed JS professionally for the last five years: sure, it has it's pain points, and the tooling/package management is somewhat of a hellscape, but on good days I kinda love it.
Avatar of Sean Fairchild

Sean Fairchild https://github.com/sfairchild

I'm a senior Ruby dev professionally at my company. I have also worked a lot with JavaScript and most recently lead a team building a React app for one of our clients.
Avatar of Phil Salant

Phil Salant https://github.com/PSalant726

I'm a full-time software engineer based in NYC. I have experience using JavaScript, React, Ruby/Rails, and Go.
Fun. Challenging. Interesting

Community-sourced JavaScript exercises

These are a few of the 99 exercises on the JavaScript track. You can see all the exercises here.

Proverb
medium
arrays
control flow conditionals
control flow loops
optional values
strings
text formatting
Forth
hard
domain specific languages
parsing
stacks
Spiral Matrix
medium
arrays
control flow conditionals
control flow loops
data structures
matrices
Roman Numerals
easy
control flow conditionals
control flow loops
pattern recognition
transforming
Isogram
easy
filtering
strings
Pig Latin
medium
control flow conditionals
control flow loops
games
regular expressions
strings
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 Tejas Bubane

Tejas Bubane My blog

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

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

Join the JavaScript Track