How can the use of PHP functions like die() and header() impact the overall user experience on a website?

Using PHP functions like die() and header() can impact the overall user experience on a website by abruptly ending the script or sending HTTP headers before the content, causing errors or unexpected behavior for the user. To prevent this, it's important to properly handle errors and headers to ensure a smooth user experience.

// Proper error handling and header usage example
if($error_condition){
    http_response_code(400); // Set HTTP response code
    die("An error occurred. Please try again later."); // Display error message and terminate script
}