JavaScript (Legacy)

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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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About JavaScript (Legacy)

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 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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I learned so much by osmosis just from reading.

Exercism has been really wonderful for me. It was the first time that I ever contributed to an open source project (it's a nice feeling knowing that when people use Exercism I may have helped them in some way), how I learned JavaScript, and how I learned about testing and TDD. I learned so much by osmosis just from reading.

Fun. Challenging. Interesting

Community-sourced JavaScript (Legacy) exercises

These are a few of the 0 exercises on the JavaScript (Legacy) track. You can see all the exercises here.

Passionate. Knowledgeable. Creative.

Meet the JavaScript (Legacy) Track maintainers

The JavaScript (Legacy) Maintainers are the brains behind the JavaScript (Legacy) 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, build, teach, repeat!
Avatar of Joel Wallis Jucá

Joel Wallis Jucá

Brazilian full-stack web developer. Mentor at Thinkful
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 (Legacy) track. As with everything on Exercism, it's 100% free!

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