# what is analog and digital signal in electrical terms? [closed]

Analog signals are continous while the digital signals. In electrical terms digital signals are like +5 volts then 0 volts again +5volts , +5volts , 0volts and so on am i right???? and the analog signals are like +5volts 4.9volts, 4.8 volts, 4.7 volts and decrease up to 0 volts and then goes negative (by the way what is negative volt) and then rises up am i right?

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Smells like homework. –  Chris S Jul 22 '10 at 20:57

## closed as off topic by Warner, Chris S♦, Zypher♦, EEAA, sysadmin1138♦Jul 22 '10 at 21:05

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Wikipedia: en.wikipedia.org/wiki/Analog_signal and en.wikipedia.org/wiki/Digital_signal with examples –  coredump Jul 22 '10 at 20:45

Analogue refers to a continuously varying quantity, so in your voltage example is partially correct - but there are an infinite number of values that it can take - usually over a range.

Digital refers to a value that can have only certain discrete values. This can be just two - 0V or +5V, but it could theoretically be more - three (-5V, 0V and +5V) for example.

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