How can I use PHP to send a header that forces the browser to pull a page from cache instead of reloading it?

To force the browser to pull a page from cache instead of reloading it, you can use the "Cache-Control" header with a value of "public" and set the "max-age" to a desired time in seconds. This tells the browser to cache the page for the specified duration before checking for updates.

<?php
header('Cache-Control: public, max-age=3600'); // Cache the page for 1 hour
?>