A free to air digital service is made up of two chartered public broadcasting companies, the BBC and Channel 4 and two franchised commercial television companies, (ITV and Channel 5) specializing in entertainment, drama, arts, science, nature, documentary, sports, comedy etc. In addition to this, the United Kingdom's free-to-air Freeview service runs a large number of entertainment, music, sport and shopping channels from the likes of CBS, UKTV and Sky. There are five major nationwide television channels: BBC One, BBC Two, ITV, Channel 4 and Channel 5 — currently transmitted by digital terrestrial, free-to-air signals with the latter three channels funded by commercial advertising.