Acknowledgements

This free course was written by Allan Jones, David Chapman, Helen Donelan, Laurence Dooley, and Adrian Poulton.

This free course includes adapted extracts from the course TM355 Communications technology. If you are interested in this subject and want to study formally with us, you may wish to explore other courses we offer in Technology.

Except for third party materials and otherwise stated (see terms and conditions [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] ), this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence.

The material included with this course is entirely the property of the Open University.

Don't miss out

If reading this text has inspired you to learn more, you may be interested in joining the millions of people who discover our free learning resources and qualifications by visiting The Open University – www.open.edu/ openlearn/ free-courses.