To hide an extension from URL, for instance;
Change this url http://simplebyte.net/does/seo.php to http://simplebyte.net/does/seo
copy and paste the following code to your .htaccess file.
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.*)$ $1.php
