MIDI stands for Musical Instrument Digital Interface (Musical Instrument Digital Interface). This is a standard serial communication protocol that allows computers, synthesizers, sequencers, controllers and other electronic musical devices to communicate and share information to generate sounds. This information defines various data types such as numbers may correspond to particular notes, numbers synthesizer patches or driver settings. Because of this simplicity, the data can be interpreted in various ways and used for purposes of music. The protocol includes additional hardware and software specifications.
RealAudio is a proprietary audio format developed by RealNetworks and first released in April 1995. It uses a variety of audio codecs, ranging from low-bitrate formats that can be used over dialup modems, to high-fidelity formats for music. It can also be used as a streaming audio format, that is played at the same time as it is downloaded. In the past, many internet radio stations used RealAudio to stream their programming over the internet in real time. In recent years, however, the format has become less common and has given way to more popular audio formats. RealAudio was heavily used by the BBC websites until 2009, though it was discontinued due to its declining use. BBC World Service, the last of the BBC websites to use RealAudio, discontinued its usage in March 2011.