What is the importance of using the method attribute in a form when working with PHP?

When working with PHP and forms, it is important to specify the method attribute in the form tag to indicate how the form data should be submitted. The method attribute can have two values: "GET" or "POST". Using the "GET" method appends the form data to the URL, making it visible in the browser's address bar, while using the "POST" method sends the form data in the HTTP request body, keeping it hidden from the user.

<form method="POST" action="process_form.php">
  <!-- Form fields go here -->
</form>