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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AIF (Audio Interchange File/Apple Interchange File Format) is a sound format used on Windows. It comes with a .aif filename extension and .aiff when used on Mac. An AIF file features raw sound data like sample rate, bit depth, and channel (mono/stereo). This file format is also accepted on most CD writers.
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