How can PHP be used to save the interpreted HTML source code of a webpage?

To save the interpreted HTML source code of a webpage using PHP, you can use the `file_get_contents()` function to fetch the webpage content and then save it to a file using the `file_put_contents()` function.

$url = 'https://www.example.com';
$html = file_get_contents($url);

if($html !== false){
    file_put_contents('saved_page.html', $html);
    echo 'HTML source code saved successfully.';
} else {
    echo 'Failed to fetch HTML source code.';
}