In signal processing, what does "latency" refer to?

Latency in signal processing specifically refers to the delay that occurs between the input of a signal and the output response produced by a system. This concept is crucial in various applications such as audio processing, video streaming, and telecommunications, where any noticeable delay can impact the effectiveness and quality of the user experience.

When evaluating the other options, it’s clear they address different aspects of signal processing. The idea of latency as the time taken for a signal to reach a destination could be misleading because it implies a one-way measurement rather than the critical measure of delay within a system. The total volume of a signal pertains to amplitude, and frequency response is about how different frequencies are handled within a system, but neither of these relates to the concept of delay in processing signals.