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

118 Mentors

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

56,769 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

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 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.
Avatar of Yash Kulshrestha

Yash Kulshrestha https://github.com/YashdalfTheGray

I've been writing Javascript for pretty much all of my career as a software engineer, professionally and for my pet projects.
Avatar of Tyll Weiß

Tyll Weiß https://github.com/Inkdpixels

I love JavaScript for it's flexibility and fast-paced community. I've written and maintained quite a bit of Node and browser oriented Javascript projects, both personally and professionally.
Avatar of Hieu Nguyen

Hieu Nguyen GitHub

I'm a javascript developer with deep knowledge in the language itself and NodeJS. Recently i started learning Python as my secondary. Java was used in the past, but no longer my primary language
Avatar of Rhys Brooker

Rhys Brooker Twitter

Front end developer working with JavaScript and ReactJS. Self taught developer, I enjoy teaching and helping others learn a new language. Contact me on Twitter if you would like more help, I love to network and help.
Avatar of Josh Morrow

Josh Morrow https://github.com/jcmorrow

I didn't feel like I understood JS for the first two years or so that I used it professionally. Once I dug into the prototypical inheritance and functions as a first-class object things really started to click, and ever since ES6 came out it's been a favorite language of mine.
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.

Matrix
easy
arrays
matrices
text formatting
conditionals
loops
Palindrome Products
medium
algorithms
exception handling
integers
math
conditionals
loops
Collatz Conjecture
easy
exception handling
integers
recursion
math
conditionals
loops
Gigasecond
easy
time
Resistor Color
easy
arrays
strings
Accumulate
medium
algorithms
callbacks
lists
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.

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Join the JavaScript Track