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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DV (Digital Video) is a file created using a digital format and saved as raw data. A DV file contains 80-byte DIFs (Digital Interface Blocks), with each block having video, audio, and metadata. DVD files use lossy compression for videos, while sounds stay uncompressed. And although it was originally meant for tape recording, DV can also save data on hard disc drives and optical discs.
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