PHP Superglobals

PHP superglobals are built-in variables always accessible in every scope. Key ones: $_GET (URL query data), $_POST (form POST data), $_SERVER (server & environment info). Always sanitize before output.

Example

<?php
// Get URL param: example.php?name=Alice
$name = htmlspecialchars($_GET["name"] ?? "Guest");

// POST form handling
if ($_SERVER["REQUEST_METHOD"] === "POST") {
    $email = filter_input(INPUT_POST, "email", FILTER_VALIDATE_EMAIL);
    if ($email) {
        echo "Valid email: $email";
    }
}

// Server info
echo $_SERVER["HTTP_HOST"];    // domain
echo $_SERVER["REQUEST_URI"]; // path
?>

PHP

Full Editor

Related Resources

PHP Reference

Complete tag & property list

PHP How-To Guides

Step-by-step practical guides

PHP Exercises

Practice what you've learned