In digital multimedia, bitrate represents the amount of information, or detail, that is stored per unit of time of a recording. The bitrate depends on several factors:
the original material may be sampled at different frequencies
the samples may use different numbers of bits
the data may be encoded by different schemes
the information may be digitally compressed by different algorithms or to different degrees
Generally, choices are made about the above factors in order to achieve the desired trade-off between minimizing the bitrate and maximizing the quality of the material when it is played.
Audio (MP3)
32 kbit/s — MW (AM) quality
96 kbit/s — FM quality
128–160 kbit/s — Standard Bitrate quality; difference can sometimes be obvious (e.g. bass quality)
192 kbit/s — DAB (Digital Audio Broadcasting) quality.
224–320 kbit/s — Near CD quality.
Other audio
800 bit/s — minimum necessary for recognizable speech (using special-purpose FS-1015 speech codecs)
8 kbit/s — telephone quality (using speech codecs)
500 kbit/s–1 Mbit/s — lossless audio as used in formats such as FLAC, WavPack or Monkey's Audio
1411.2 kbit/s — PCM sound format of Compact Disc Digital Audio
Video (MPEG2)
16 kbit/s — videophone quality (minimum necessary for a consumer-acceptable "talking head" picture)
128 – 384 kbit/s — business-oriented videoconferencing system quality
1.25 Mbit/s — VCD quality
5 Mbit/s — DVD quality
15 Mbit/s — HDTV quality
36 Mbit/s — HD DVD quality
54 Mbit/s — Blu-ray Disc quality
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