Here are entered works on the communications industries treated collectively. Works on human communication, including both the primary techniques of language, pictures, etc. and the secondary techniques, such as the press and radio, are entered under Communication. Works on the modern means of mass communication are entered under Mass media.
--subdivision Communication systems under names of individual military services, e.g. United States. Navy--Communication systems; and subdivision Communications under individual wars, e.g. World War, 1939-1945--Communications
--subdivision Communication systems under types of industries, institutions, installations, names of disciplines, and individual corporate bodies, e.g. Aeronautics--Communication systems; Electric power systems--Communication systems
