Gravatar stands for Globally Recognized Avatar. It is globally recognized because millions of people and websites use them. To know more about Gravatar, you can visit https://en.gravatar.com.

To use Gravatar image as favicon on your WordPress site, add the following code in your theme’s functions.php file.

// Add the following code in theme's functions.php file to use Gravatar image as favicon (16x16 favicon.ico)
function dcg_gravatar_favicon() {
    // Replace email here
    $GetEmailHash = md5(strtolower(trim('me@dipakgajjar.com')));
?>

<link rel="shortcut icon" href="<?php echo 'http://www.gravatar.com/avatar/' . $GetEmailHash . '?s=16;'; ?>" type="image/x-icon" />

<?php
}
add_action('wp_head', 'dcg_gravatar_favicon');