RA is a streaming audio file category format designed to play audio over a wide area network. The RA (RealAudio) file format was developed by RealNetworks in the mid-90s of the last century. The file itself contains encoded audio information, but it may also contain links to audio content. It may contain audio data or reference an audio streaming file. In order to compress the data, they use their own Real compression algorithm with a variable bitrate, as well as a variety of codecs. The .ra file format is a common format required to play streaming audio on the Internet. Real Audio is a standard format for playing audio clips in a web browser. As a rule, they use the RealOne Player to play it. However, due to the fact that it is completely unsuitable and clogged with advertising, they recommend the RealAlternative package. Previously, most radio stations broadcasting online used this particular format. Also until 2009, the format was used on its website by BBC. Currently, the RA format is not so popular among those who broadcast online, since new technologies have already been introduced.
MKA is an audio container format. It supports some types of audio compression algorithms. The .mka file extension belongs to the Matroska format (Matröška, Matryoshka). Thus, it serves to specifically designate the file type "Matroska Audio File" (Matroska Audio File). Matroska is an open cross-platform standard. It is a modern extensible multimedia container format. It is error resistant. It is suitable for streaming HTTP / RTP. Supports multiple subtitle tracks, audio, video. The Matroska standard is supported in the native mode by many software players and hardware devices, including, for example, receivers, televisions, smartphones, etc. A .mka file is a regular Matroska container that has one or more audio tracks. They are encoded by any of the supported codecs. In most cases, AAC and AC3 (Dolby Digital) codecs are used. Playing a .mka file needs the support of the standard Matroska container format. But not only. There must also be a specific audio codec with which the tracks are encoded. Often, MKA files are used as external audio tracks for movies in other languages. Or with other content, or with sound quality. Say multi-channel sound, director’s comments. .Mka audio files are used as containers for high-quality multi-channel music.