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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According to YouTube, MP4 video format with AAC audio codec and H.264 video codec is most recommended. However, this platform is also compatible with formats such as MOV, AVI, WebM, FLV, 3GPP, WMV, and more. Also, keep in mind that the maximum file size for YouTube is 128GB or 12 hours of playtime. So, you can use a video editor like Wondershare UniConverter to compress before uploading videos to YouTube.
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