RMVB (RealMedia Variable Bitrate) is a digital variable bitrate extension for the RM (RealMedia) container format. Unlike the standard RM format that streams content in CBR (Contant Bitrate), the RMVB, as the name suggests, streams local media in VBR (Variable Bitrate). This file format uses a .rmvb filename extension.
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MP3 is a standard audio format developed by Moving Picture Experts Group and uses MPEG-1 and MPEG-2 standardizations. MP3 uses lossy data compression, meaning that it loses quality over time. This sound format comes with a .mp3 filename extension and is today the most common audio format on websites and multimedia players.
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