BS 8521:2009

Digital - A system that uses only 0s and 1s to transmit data

Alarm - A device which emits a sound at a pre-set time/event

Frequency - A term used to describe how often something is done

Frequency - A wave frequency is the number of times a wave repeats within a given time

Telephone - A device used for communicating audio over long distances

Equipment - A product or good that is tactile.

Specification - A description of a product with the details of its attributes.

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