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.
M4A is a filename extension for AAC container format and is developed by Apple Inc. M4A music is bought on the iTunes Store and does not come with DRM protection. In terms of quality, M4A is better than MP3 because it is lossless but still compressed. This means that it occupies less storage space and doesn’t lose quality over time.
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