M4P (MPEG-4 Protected) is a digital audio file extension for the AAC (Advanced Audio Codec) container format. It uses lossy compression and is an audio-only file. In most cases, M4P files are purchased on Apple iTunes, which means they are DRM-protected. M4A is the unprotected version of M4P.
OGG is a free audio container format developed by Xiph.Org Foundation. Its unrestricted design offers efficient manipulation and streaming of high-quality digital multimedia. It multiplexes multiple streams for video, audio, text, and metadata. OGG has a filename extension of .ogg, although it can also come in .ogv, .oga, .ogm, .opus, and .spx.
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