Adding a favicon to your site (including at the root)

function.php

<?php
function emw_add_favicon () {
    echo '<link rel="shortcut icon" type="image/vnd.microsoft.icon" href="'.get_stylesheet_directory_uri().'/assets/images/favicon.ico">'."\r\n";
    echo '<link rel="icon" type="image/vnd.microsoft.icon" href="'.get_stylesheet_directory_uri().'/assets/images/imgfavicon.ico">'."\r\n"; // Shouldn't be necessary, but added for maximum browser compatibility
}
add_action('wp_head', 'emw_add_favicon');
?>