RM is a video file format developed by RealNetworks. It uses the RealPlayer player, that is, a program for streaming audio and video files. The format contains audio and video data or links to streaming, which can be played back as it downloads. The RealMedia Player program was in great demand when they connected to the Internet using a modem, and when there was practically no broadband access to the global network. The large compression ratio of the format provided the opportunity to carry out online transmission of video and audio data. The quality of the output file, as a rule, was low. Today, such files are often used in order to broadcast Internet radio and Internet video. In the .RM format, music and video are found on the global network or on Western cable channels, on Internet radio stations. Support for this format is carried out by such mobile phones and smartphones as Nokia, Ericsson, Sony, iPhone, as well as mobile devices that operate on the Google Android operating system. Files with the extension .RM are compressed using proprietary codecs RealVideo and RealAudio. Individual Real Media files can be played using a VLC media player that partially supports RM files.
MPGA is one variation of the common digital audio file format (or MPEG Audio). The full name of this format is MPEG-1 Layer 3 Audio File. MPGA format is considered standard for Windows and is supported by all players of this operating system. Any multimedia software that supports MP3 format can work with MPGA audio files. MPGA files are small in size and have significant compression, and file compression is performed without loss of quality and preserving the original sound. The massive use of MPGA is related to the Android mobile OS.