WMV (Windows Media Video) is a collection of video codecs with their respective coding formats introduced by Microsoft on its Windows Media framework. Initially, it was designed to compete with RM format on online streaming apps. It stores compressed videos and is even used to deliver content on Blu-ray/DVDs.
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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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