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.
MKA is a free Matroska Multimedia Container format that can store multiple audio, video, image, and subtitle tracks. It’s used to save typical multimedia content such as TV shows and movies and comes with a .mkv for video files. When used on audio files, it features a .mka filename extension, .mks for subtitles, and .mk3d for stereoscopic video files.