How can an icon be inserted instead of a pixel using PHP?

To insert an icon instead of a pixel using PHP, you can use an HTML tag with the appropriate class or ID that references the icon's CSS. This can be achieved by including a CSS file that contains the icon styles, such as Font Awesome or Material Icons, and then applying the corresponding class to the HTML element where you want the icon to appear.

<!DOCTYPE html>
<html>
<head>
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.4/css/all.min.css">
</head>
<body>
  <i class="fas fa-user"></i> <!-- This will display a user icon -->
</body>
</html>