Digital audio processing/Analysis
Signal processing is the act of analyzing, modifying, or generating signals. The first of these processes, analysis, is a powerful tool for understanding not only the properties of the signal itself, but also the system that created it.
For example, by taking a recording of a person speaking, a signal processor could use various analytical techniques to determine the phonemes that the person was speaking, which is the first step to recognizing that person's speech. However, given enough data, it could also determine the shape and size of the person's vocal tract is, approximating attributes like height or weight from just the audio data.