The topic of data networks falls under the more general area of data communications. Data communications has roots in both telecommunications and computer science. Telecommunications is a broad topic area with relevance to healthcare. Doctors, nurses, and patients have been using telephones and telephone networks to talk to each other since the beginning of telephone service. Ambulances have used radio networks to communicate to hospitals to inform them of the state of patients in their care. Television networks have been used to inform citizens about the status of epidemics. The Internet and wireless networks of tomorrow have the potential to radically change the way healthcare is delivered.