Node.js

Node.js is a JavaScript runtime environment that runs in the terminal.

It exists because:

• Websites use JavaScript
• which runs in the browser
• and they're getting more and more complicated
• so we'd like to write and test JavaScript outside the browser.

Browsers use other JavaScript "engines" like V8 and SpiderMonkey. These engines need to be "sandboxed" so they can't do nasty things to your computer, because your browser happily runs anything it sees on the internet.

Node.js isn't sandboxed, so it can do things that they can't, like read and write files. But there are also things that browser-based engines do that wouldn't make sense for Node.js. For example: because Node.js runs in the terminal, it doesn't have an actual webpage to play with, so it doesn't have the Window API.

Installing

Check the download page.

Unless you have a specific reason, you should use NVM, "Node Version Manager". (If you're using WSL, select the Linux option.)