what is in the post php code example

Example 1: php post

<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
  Name: <input type="text" name="fname">
  <input type="submit">
</form>
<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
  // do logic
  $name = $_POST['fname'];
}
?>

Example 2: post request php

$response = httpPost("http://mywebsite.com/update.php",
	array("first_name"=>"Bob","last_name"=>"Dillon")
);

//using php curl (sudo apt-get install php-curl) 
function httpPost($url, $data){
    $curl = curl_init($url);
    curl_setopt($curl, CURLOPT_POST, true);
    curl_setopt($curl, CURLOPT_POSTFIELDS, http_build_query($data));
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    $response = curl_exec($curl);
    curl_close($curl);
    return $response;
}