Core Web Technologies

JavaScript

The programming language of the web.

Definition

The programming language of the web. It runs in the browser and makes web pages interactive — handling clicks, updating content without reloading, fetching data from APIs, and responding to user input in real time.

Example

button.addEventListener('click', function() { alert('You clicked!'); }); — this JavaScript code shows a popup when someone clicks a button.

See it in context Learn how JavaScript fits into the bigger picture of how software actually works.

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