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

63 Mentors

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

20,290 Students

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

94 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 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 Michal Bryxí

Michal Bryxí Ultimate useless project

I love providing users with delightful UX. I love automating things. I hate computers.
Avatar of Nada Ghanem

Nada Ghanem https://github.com/nadaa

A continous learner, love technology and nature.
Avatar of John Turner

John Turner https://github.com/johndturn

I've been working professionally with JavaScript for about 4 years. I currently help manage the FrontEnd team at Bento for Business, working in Angular, Ionic, and React. I also maintain a large-scale React SPA as a long-running side project. I'm excited to share what I've learned in my time with JavaScript, and learn from others as well!
Avatar of Cameron MacDonald

Cameron MacDonald GitLab

I write JS professionally, and I also write JSX in Reactjs, so I've got plenty of experience with this and I'm happy to show you the ropes!
Avatar of Aleksander Heintz

Aleksander Heintz My blog

I love programming, and do it both professionally and as a hobby. At work I do most javascript and typescript, but I've also done a lot of F# and C#.
Fun. Challenging. Interesting

Community-sourced JavaScript exercises

These are a few of the 94 exercises on the JavaScript track. You can see all the exercises here.

Matrix
medium
arrays
control flow conditionals
control flow loops
data structures
matrices
text formatting
Proverb
medium
arrays
control flow conditionals
control flow loops
optional values
strings
text formatting
Protein Translation
easy
algorithms
control flow conditionals
control flow loops
strings
Wordy
medium
control flow conditionals
control flow loops
exception handling
parsing
pattern recognition
regular expressions
strings
Twelve Days
medium
control flow conditionals
control flow loops
pattern recognition
polymorfism
regular expressions
strings
Triangle
easy
control flow conditionals
control flow loops
exception handling
integers
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 Matt Morgan

Matt Morgan

Learn, teach, build, repeat!
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

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

Join the JavaScript Track