How can server-side or JavaScript techniques be used to prevent browser errors when using the "Back" button on a PHP-generated page?

When using the "Back" button on a PHP-generated page, browser errors can occur due to cached data or expired sessions. To prevent this, you can use server-side techniques like setting proper cache control headers or JavaScript techniques like disabling caching. By ensuring that the browser fetches the most up-to-date content from the server, you can mitigate these errors.

// Prevent caching of PHP-generated pages
header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past

// Prevent browser from caching JavaScript files
echo '<script> window.onunload = function(){} </script>';