How to change the page title and description when .header.php included

[Mittineague]

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How to hide the .php extensions from the Url

How to hide .php extension. I have already applied a rule in .htaccess. Now the information in url can display with our without php extension. But am looking for some code that i can hide the extension so users cannot see it. Can someone can help me out. EDIT continued from https://www.sitepoint.com/community/t/how-to-change-the-page-title-and-description-when-header-php-included/288064 (Mittineague)