Which type of signal has discrete values of on or off?

A digital signal is characterized by discrete values, typically represented as binary states of on (1) and off (0). This kind of signal operates in a two-level system, meaning it has specific, distinct states that correspond to these values.

Digital signals are essential in modern telecommunications and computer systems because they provide a clear and precise way to encode and transmit information. Their discrete nature allows for easier error detection and correction compared to analog signals, which can vary continuously and may represent a range of values. In digital signal processing, the transition between on and off states can be quickly and accurately interpreted by electronic devices, making such signals highly reliable for transmitting information over various media.

In contrast, an analog signal does not have discrete values; it represents information in a continuous waveform, which can vary infinitely within a range. Resistance refers to the opposition encountered by current in an electrical circuit, and crosstalk relates to interference between circuits. These concepts do not inherently describe the on/off characteristic associated with digital signals.