No magic. "www-nlp" and "www" are explicitly configured to point to the same IP address in the DNS. Then (in the simplest case) the responding webserver is con

No magic. "www-nlp" and "www" are explicitly configured to point to the same IP address in the DNS. Then (in the simplest case) the responding webserver is configured to treat the two hostnames (and possibly others) as identical and serve the same files. So I guess there is magic. CNAMEs and virtual hosts and HTTP1.1.