WebM is an open-source, royalty-free multimedia format for streaming content online. It contains compressed video streams of either VP8 or VP9 codec and compressed audio streams of Oupus or Vorbis codec. Today, it’s one of the most widely used file formats to stream videos online because of its lightweight and real-time delivery nature.
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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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