AAC (Advanced Audio Coding) is a lossy audio format developed by Dolby and Sony Corporation, AT&T Bell Laboratories, and Fraunhofer IIS. During compression, AAC eliminates unnecessary data, making it smaller and easier to stream or download. Today, Apple devices such as iPhones and iPads are the biggest users of the AAC format.
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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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