What is the significance of using $_REQUEST in PHP code?

Using $_REQUEST in PHP code allows you to retrieve data from both the $_GET and $_POST arrays, making it a versatile option for handling form data. However, it is important to use $_REQUEST carefully as it can make your code vulnerable to security risks such as cross-site scripting (XSS) attacks. To mitigate these risks, it is recommended to validate and sanitize user input before using it in your code.

// Example of using $_REQUEST with input validation and sanitization
$username = isset($_REQUEST['username']) ? htmlspecialchars($_REQUEST['username']) : '';
$email = isset($_REQUEST['email']) ? filter_var($_REQUEST['email'], FILTER_SANITIZE_EMAIL) : '';