The main language of JavaScript consists of a long list of programming features that allow you to do many actions to your website. For example, JavaScript is used to run code in response to certain events happening on the web page. If you used a "click" event in your code, it would detect when a button is clicked and run the specific action. The Javascript is then telling websites or apps to do something in real-time, without having to reload the entire page, making interactions more efficient.