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Demo 2.3

JavaScript is for functionality

Files in this demo

├─ index.html
├─ style.css
└─ script.js

HTML gives a page content and CSS makes it look good — but so far the page just sits there. JavaScript makes a page do things in response to the visitor.

JavaScript can listen for events (like a click), remember information in variables, and change the page while it’s running. Here, clicking the button runs a small function that adds one to a counter and updates the text below it.

JavaScript goes inside a <script> element. Click the button in the preview to try it!

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