DAN - Divers Alert Network a nonprofit scuba diving and dive safety association providing expert medical advise for underwater injuries, emergency information, research, training and products.
HTTP Header reponses of diversalertnetwork.org is the information we get when HTTP request sent to a server from connecting clients(e.g. chrome, firefox). When you input an address into your browser it sends a request to the server hosting the domain and the server responds. HTTP Header information is not directly displayed by normal web browsers like chrome, firefox etc.