MP2 (MPEG Audio Layer 2) is a Moving Picture Experts Group audio format that comes with a .mp2 filename extension. Like MP3, MP2 is a lossy format and is mostly used for sound broadcasting. Because a limited number of audio players support MP2, it’s best to convert it to MP3, which is a universal format.
ASF (Advanced Systems Format) is a digital multimedia format designed to save and open content online. It is the primary container for Windows Media Video and Windows Media Audio content. Today, ASF supports smooth playback on HTTP servers, media servers, and local storage with programs like Windows Media Player.