MP3 Last modified: Friday, October 27, 2006
The name of the file extension and also the name of the type of file for MPEG, audio layer 3. Layer 3 is one of three coding schemes (layer 1, layer 2 and layer 3) for the compression of audio signals. Layer 3 uses perceptual audio coding and psychoacoustic compression to remove all superfluous information (more specifically, the redundant and irrelevant parts of a sound signal. The stuff the human ear doesn't hear anyway). It also adds a MDCT (Modified Discrete Cosine Transform) that implements a filter bank, increasing the frequency resolution 18 times higher than that of layer 2. The result in real terms is layer 3 shrinks the original sound data from a CD (with a bit rate of 1411.2 kilobits per one second of stereo music) by a factor of 12 (down to 112-128kbps) without sacrificing sound quality. Because MP3 files are small, they can easily be transferred across the Internet.
MP3 Resources  Provides numerous resources related to MPEG Audio Layer 3. MP3.com  Resource site for news and information about MP3. Includes a question and answer section, information about hardware and software, and links to related sites. 32-bit MP3 Players Collection of reviewed, rated and downloadable MP3 players from Stroud's CWSApps. MP3 Articles Collection of ongoing articles about MP3 from Wired News. MP3now.com Contains links to the top MP3 search engines and charts, software, hardware, downloads, and overview information. The Digital Media Association The Digital Media Association includes other Web-media technology and retail companies, such as a2b music, broadcast.com, CDnow, Enso Audio Imaging, Liquid Audio, RealNetworks, and TCI Music. Yahoo!'s MP3 page Yahoo!'s directory of MP3.	Related Categories Audio Data Compression Related Terms AAC data compression digital audio MP3 player MPEG shop.internet.com Products MP3 Players 104 deals Below $40 113 deals $40 - $60 144 deals $60 - $100 125 deals $100 - $180 129 deals Above $180 More shop.internet.com Deals MP3 Players MP3 Products Shop by Top Models: Apple iPod touch (16 GB, MA627LL/A) Digital Media Player 7 store offers from $270 - $401 Apple iPod nano Third Gen. Silver (4 GB, MA978LL/A) Digital Media Player 3 store offers from $110 - $120 Apple iPod classic Sixth Gen. Black (160 GB, MB150LL/A) Digital Media Player 1 store offers from $300 - $300 Apple iPod classic Sixth Gen. Black (80 GB, MB147LL/A) Digital Media Player 2 store offers from $200 - $220 Apple iPod nano Third Gen. Green (8 GB, MB253LL/A) Digital Media Player 8 store offers from $125 - $139