MP3 is still easily the most widly used and widely supported digital audio file format. As a result, working with MP3 tends to be simple, especially on Linux. There was a time when it was still a proprietary format, and required additional packages, but now, converting your MP3 files is a breeze.
This is a companion discussion topic for the original entry at https://linuxconfig.org/how-to-convert-to-and-from-mp3-on-linux