Why is the use of frames in PHP considered questionable, and what are the alternatives for dividing windows without frames?

Using frames in PHP is considered questionable because it can lead to issues with accessibility, SEO, and overall user experience. Instead of frames, developers can use PHP includes or AJAX to divide windows without frames. PHP includes allow you to separate your code into different files and include them where needed, while AJAX enables you to load content dynamically without refreshing the entire page.

<?php include 'header.php'; ?>
<div id="content">
  <!-- Your main content here -->
</div>
<?php include 'footer.php'; ?>