How can one efficiently handle string manipulations for simple encryption purposes in PHP?

When handling string manipulations for simple encryption purposes in PHP, one efficient way is to use built-in functions like `str_rot13()` for basic encryption. This function rotates the characters in a string by 13 positions, providing a simple encryption method. To encrypt a string using `str_rot13()`, simply pass the string as an argument to the function.

// Encrypt a string using str_rot13()
$string = "Hello, World!";
$encryptedString = str_rot13($string);

echo $encryptedString; // Outputs "Uryyb, Jbeyq!"