Telecommunications includes telephone systems and all forms of data transmission conveyed through the agency of electric, magnetic, electro-magnetic, electro-chemical or electro-mechanical energy.  Operation of telecommunication systems is regulated by licensing powers of the Secretary of State and the Director General of Telecommunications under the Telecommunications Act 1984.
Wireless telegraphy is defined in legislation as emitting or receiving (without wires) electromagnetic energy of a frequency not exceeding 3 million megacycles per second. The Secretary of State has the power to make regulations concerning wireless telegraphy and to licence operators.  These powers extend to the use of the radio spectrum.  There is an overlap with Broadcasting which is regulated under separate legislation which is also reserved.
The reservation extends also to the subject-matter of a number of EC Directives and Regulations dealing with telecommunications and wireless telegraphy which use definitions which have a similar effect to those cited in UK legislation.  This includes the regulations concerned with electromagnetic disturbance which is in part concerned with the establishment and regulation of technical standards.  Technical standards of goods are also reserved.
Internet services are provided over computer systems linked by national and international telephone system but the services provided go beyond ordinary telecommunications.  The reservation extends to all such services provided by electronic means at a distance.
Electronic encryption covers the general use of encryption of communications or data in electronic form for the purposes of commercial confidentiality and authentication.
TABLE OF RESERVED MATTERS Head C: Trade and Industry General