OGG is a free audio container format developed by Xiph.Org Foundation. Its unrestricted design offers efficient manipulation and streaming of high-quality digital multimedia. It multiplexes multiple streams for video, audio, text, and metadata. OGG has a filename extension of .ogg, although it can also come in .ogv, .oga, .ogm, .opus, and .spx.
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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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