script tags, external files and placement.
✍️ 3 exercises + code challenge in this lessonJavaScript code is placed in a <script> element. It can go in the <head>, in the <body>, or in an external file.
<script src="app.js"></script> loads code from a separate file. This keeps HTML and JavaScript apart, and browsers can cache the file.
<body>, or use <script src="app.js" defer> in the head, so the HTML loads first.Mastering JavaScript Where To 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.
<!DOCTYPE html>
<html>
<head>
<script>
function greet() {
document.getElementById("msg").innerHTML = "Function defined in the head.";
}
</script>
</head>
<body>
<p id="msg">Click the button.</p>
<button onclick="greet()">Try it</button>
<script>
// Code at the end of the body runs after the HTML above exists
document.body.style.fontFamily = "Arial";
</script>
</body>
</html>Check what you learned in “JavaScript Where To”.
Load JavaScript from an external file.
<script ="app.js"></script>
Which attribute makes an external script run after the HTML has loaded?
Add a <script> that sets the page background to "lightyellow".
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