How can cookies set on a web page affect the functionality of a PHP script that extracts data from that page?

When cookies are set on a web page, they can affect the functionality of a PHP script that extracts data from that page by potentially altering the content or behavior of the page based on the cookie values. To ensure the PHP script extracts data accurately, you can use the `CURLOPT_COOKIEFILE` option in a cURL request to include the cookies set on the web page in the request.

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'https://example.com/page_with_cookies');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIEFILE, 'cookies.txt'); // Specify the file containing cookies
$output = curl_exec($ch);
curl_close($ch);

// Extract data from the page
// Your data extraction code here