You know, we would not be able to use VoIP and have cheap international phone calls without audio compression codecs.
It’s plenty of them, some royalty free, some patented by telco’s lobby (think that some patented and royalty-based codec it’s also a standard, where all market player have to pay the most aggressive one that acquired the patent while defining the standards).
However, there is a nice collection from vocal, to understand how they sounds.