How can the use of cookies in PHP impact the overall performance and user experience of a website?

The use of cookies in PHP can impact the overall performance and user experience of a website by increasing the amount of data being transferred between the client and server, potentially slowing down page load times. To mitigate this impact, it is important to only store essential information in cookies and limit the size of the data being stored.

// Set a cookie with essential information
setcookie("user_id", $user_id, time() + 86400, "/");