MBR, or multi-bitrate, is a way of encoding audio or video files so that they can be played back at different bitrates, or the amount of data transferred per second. This allows for smoother playback on devices with varying connection speeds, as the file can adapt to the available bandwidth. MBR encoding is commonly used for streaming media, as it allows the playback to be adjusted on the fly to ensure the best possible quality .
Some MBR encoded files may have multiple bitrate versions of the same content, allowing for high quality playback on fast connections and lower quality playback on slower connections (i.e.144p, 240p, 480p, 720p, 1080p and so on).