What is the significance of using the "required" attribute in HTML5 when handling form validation in PHP?

The "required" attribute in HTML5 is used to ensure that a form field must be filled out before submitting the form. This attribute helps in client-side validation to prevent the form from being submitted with empty required fields. To handle form validation in PHP, you can check if the required fields are not empty before processing the form data on the server-side.

if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $name = $_POST["name"];
    $email = $_POST["email"];
    
    if (empty($name) || empty($email)) {
        echo "Please fill out all required fields.";
    } else {
        // Process the form data
    }
}