How can the use of header() and exit() functions impact the overall performance and efficiency of a PHP program?

Using the header() and exit() functions in PHP can impact the overall performance and efficiency of a program by prematurely ending the script execution and preventing any additional processing. This can be useful for redirecting users or handling errors, but it should be used judiciously to avoid unnecessary disruptions to the program flow.

// Example of using header() and exit() functions
header("Location: https://www.example.com");
exit();