Signals can either be analogue or digital. In an analogue signal, the signal is varied continuously with respect to the information. In a
digital signal, the information is encoded as a set of discrete values. Ones and zeros. During transmission, the information contained
in analogue signals will be degraded by noise. Conversely, unless the noise exceeds a certain threshold, the information contained in
digital signals will remain intact. This represents a key advantage of digital signals over analogue signals.

Networks

A collection of transmitters, receivers or transceivers that communicate with each other is known as a network. Digital networks may
consist of one or more routers that route data to the correct user. An analogue network may consist of one or more switches that
establish a connection between two or more users. For both types of network, repeaters may be necessary to amplify or recreate the
signal when it is being transmitted over long distances. This is to combat attenuation that can render the signal indistinguishable from
noise.

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