HTML forms can submit data using either the GET or POST HTTP method. Understanding the difference is fundamental to writing correct and secure web applications.
<?php
// Access GET parameters ($_GET superglobal)
// URL: /search.php?query=php&page=2
$query = $_GET['query'] ?? '';
$page = (int) ($_GET['page'] ?? 1);
echo "Searching for: " . htmlspecialchars($query);
echo "Page: $page";
// Access POST parameters ($_POST superglobal)
// Submitted from <form method="post">
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
$username = $_POST['username'] ?? '';
$password = $_POST['password'] ?? '';
echo "Login attempt for: " . htmlspecialchars($username);
}
// $_REQUEST merges GET, POST, and COOKIE — avoid it
// It can be a security issue since origin is ambiguous
// Check which method was used
$method = $_SERVER['REQUEST_METHOD']; // "GET" or "POST"
echo "Method: $method";
Tip: Never use GET for actions that modify data (deletes, updates, payments). A search engine crawler or a pre-fetching browser could trigger destructive operations by following GET links.