What JavaScript can do.
✍️ 3 exercises + code challenge in this lessonJavaScript is the programming language of the web. Together with HTML (structure) and CSS (style), it adds behaviour to web pages.
JavaScript also runs outside the browser, on servers (Node.js) and in mobile and desktop apps.
Mastering JavaScript Introduction helps you write clean and reliable JavaScript code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
<h2 id="demo">JavaScript can change this text.</h2>
<img id="bulb" src="https://picsum.photos/id/1/120/80" alt="Picture" width="120" height="80">
<br>
<button onclick="document.getElementById('demo').innerHTML = 'Hello JavaScript!'">Change text</button>
<button onclick="document.getElementById('demo').style.color = '#2563EB'">Change colour</button>
<button onclick="document.getElementById('bulb').style.display = 'none'">Hide image</button>Check what you learned in “JavaScript Introduction”.
Change the content of the element with id "demo".
document.getElementById("demo"). = "Hello";
JavaScript is mainly used to…
Change the text of the <h2> to "Hello JavaScript!".
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