What are the differences between using include/require and fsockopen() for executing scripts in PHP?

When including or requiring files in PHP, the code within those files is executed in the same scope as the calling script. On the other hand, fsockopen() allows you to establish a network connection to a remote server and execute scripts on that server. The key difference is that include/require is used for local file inclusion, while fsockopen() is used for remote script execution.

// Using include/require for local file inclusion
include 'myfile.php';
// OR
require 'myfile.php';

// Using fsockopen() for remote script execution
$fp = fsockopen("www.example.com", 80, $errno, $errstr, 30);
if (!$fp) {
    echo "$errstr ($errno)<br />\n";
} else {
    fwrite($fp, "GET /myscript.php HTTP/1.0\r\nHost: www.example.com\r\n\r\n");
    while (!feof($fp)) {
        echo fgets($fp, 128);
    }
    fclose($fp);
}