What is the purpose of using urlencode or rawurlencode in PHP when passing data to a URL?

When passing data to a URL in PHP, it is important to properly encode the data to ensure that special characters are handled correctly and do not cause issues with the URL structure. urlencode and rawurlencode are functions in PHP that can be used to encode data before including it in a URL. urlencode is more suited for encoding data to be included in a query string, while rawurlencode is more aggressive in encoding characters, making it suitable for encoding entire URLs.

// Using urlencode to encode data before passing it to a URL
$data = "Hello World!";
$encoded_data = urlencode($data);
$url = "https://example.com/?data=" . $encoded_data;
echo $url;