MP3 is a digital music format used for creating high-quality sound files. Playback is widely supported by most computers, modern DVD players (via disc or usb drive) and portable devices (such as iPods and smartphones).
If you find that you cannot play mp3 files, then you may need to download an MP3 player. There are dozens of players available, and most of them are free in various desktop and mobile app stores. Alternatively, search your devices official supplier or manufacture website.