There are three types of sound content; spoken word, music and other sounds. The carriers used for sound recordings are the same, whatever the content.
Recordings of the human voice fall into groups:
These are recordings of performances of musical works. Musical works may be for single or multiple instruments, single or multiple voices or combinations of voice(s) and instrument(s). Some musical works are created using digital techniques.
Various types of sound other than the spoken word and music have been recorded - animal noises, machinery sounds (e.g. a steam train), natural sounds (e.g. waves) - either to make a permanent record or for use as sound effects in films and broadcasts, etc.
A large range of carriers have been used to hold sound recordings.