MP2 is an extension of compressed MPEG Layer II audio files. This type of file is still the standard format for digital television and radio. However, most users prefer the MP3 format. The MP2 file is compatible with most portable audio players. We emphasize that for certain devices it is necessary to convert MP2 files to MP3 format. Note that MP2 files are not identical to MPEG-2 video files. Typically, an MPEG-2 video file is used as an MPG extension. In some cases, MP2 files are called musicam files, which cannot be considered correct. In the 80s of the last century, specialists developed many versions of MP files. It was then that the developers of the International Standardization Organization Moving Picture Experts Group (MPEG) were engaged in new standards for digital encoding of audio and video data. Part of the initial release of the MP1 files were 3 separate layers of the audio file. In the 90s, they developed the MP2 format. To this day, this format is used for digital television and radio broadcasting. Due to its broad support for MPEG-1, MP2 files can be played, saved, converted and edited by a multitude of multimedia players and audio editors on a wide variety of platforms and operating systems.
M4R is a highly specialized audio file format. This format (full name - iPhone Ringtone File) was developed by Apple's IT giant specifically for the iPhone. This format creates music ringtones for the iPhone. ITunes Ringtone is the main program for opening files with the extension .m4r, and their creation is mainly using Apple iTunes. Formally, M4R files can only be created from songs and other works purchased in the iTunes music store. The size of the created ringtone in the M4R format can be a maximum length of not more than 40 seconds.