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Define analog and digital signals

Short answer

An analog signal varies continuously in amplitude (e.g., voice waveform); a digital signal has discrete voltage levels representing bits, such as 0 V and 5 V in a computer.

Define analog and digital signal with example.

Analog signal: a signal whose amplitude varies continuously with time and can take any value in a range. Examples: the human voice picked up by a microphone, a sine wave, a temperature sensor output.

Digital signal: a signal that has only a limited number of discrete levels, usually two (for binary 0 and 1). Examples: the voltages (0 V and 5 V) in a computer, pulses on an Ethernet cable.

Analog:   /\    /\        Digital:  _____     _____
         /  \  /  \  ...            |     |___|     |__
        /    \/    \

✓ Answer checked by Claude Opus 5.5 (high effort)

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