CD, short format of Compact Disc, is a digital optical disc data storage format. An Audio CD is a music CD like that you buy in a music store for play on CD player.
Music is stored on Audio CDs can be MP3, or uncompressed digital data with no data lost, exactly as in WAV digitally encoded files. In a process known as ripping, Windows Media Player in Windows 10 can copy your CDs to your PC as MP3 files, the industry standard for digital music.