When you click to view a pdf file on a page the url is always this: http://yoursite.com/sites/default/files/myfile.pdf. You can modify this path in the field setting and add tokens, dates. But what if you wants the url to be simple and not give out the fact that this is a Drupal site. Can you change it to be this: http://yoursite.com/files/myfile.pdf. Does this require htaccess url rewrite or Apache redirects?
Go to this path
/admin/config/media/file-system, and change the public file system path.
It might be this,
sites/default/files, change it to
Then create a writeable folder in your webroot called files.
This could also be done by adding this line in the settings.php file:
$settings['file_public_path'] = 'files';
Just note that this is only for local development if you want to deploy this change you might use the above solution and then export the configuration.