JavaScript in <head>

In this example, a JavaScript function is placed in the <head> section of an HTML page. The function is invoked (called) when a button is clicked:

HTML file:	Displayed by browser:
<!DOCTYPE html> <html> <head> <script> function myFunction() { document.getElementById("demo").innerHTML = "Paragraph changed."; } </script> </head> <body> <h1>My Web Page</h1> <p id="demo">A Paragraph</p> <button type="button" onclick="myFunction()">Try it</button> </body> </html>	My Web Page A Paragraph

HTML file:

Displayed by browser:

<!DOCTYPE html>
<html>

<head>
<script>
function myFunction() {
document.getElementById("demo").innerHTML = "Paragraph changed.";
}
</script>
</head>

<body>
<h1>My Web Page</h1>
<p id="demo">A Paragraph</p>
<button type="button" onclick="myFunction()">Try it</button>
</body>
</html>

My Web Page

A Paragraph