All sounds in nature are analog signals.
Analog information holds information from all consecutive times. Since it is not possible to record all the values at all times, usually only the values at regular time intervals are recorded. That is, you need to set a reasonable time interval for extracting values.
To accurately record analog information as digital information, the time interval for recording must be sufficiently small. In other words, it should be recorded at tighter time intervals than the specific time when analog information changes. It would be nice to do it indefinitely, but there are limitations in storage capacity and processing speed, so you have to compromise at an appropriate level.