Why is mp3 called lossy format?

[black hawk]

I've heard that songs in mp3 format lose some quality each time they are played. Does this mean literally, that after 1000th time I hear the song, i will find a great difference in the quality of the song?

[SilentTrigger]

It wont change when you play it, but when high quality audio is converted to mp3 it will lose quality, if you convert a mp3 file once again to mp3 you will lose more information yet again. In other words a lossy format. The reason information is lossed is because the data is compressed, in other words all the information that was in the original audio file is no longer in the mp3 file only a fraction of the original information is transfered to the mp3 file

FLAC is another audio format that is a lossless format, in other words it won't lose information (quality) when converted from WAV for example. FLAC is however smaller then WAV and that's the reason that FLAC was made, to save space but not lose quality. FLAC is however larger files then that of mp3 FLAC is also compressed but in a smarter way, you arrange the information in another structure which makes it possible to use fewer 1 & 0es to get the same information out. Bit hard to explain

Just some random information:
How do you know that FLAC is lossless? Because FLAC stands for Free Lossless Audio Codec

[atholon]

Good explanation ST.

Digital data shouldn't lose any quality unless it is compressed like ST said. That is one of the benefits of digital data over analog.

[chopperprop]

I use Advanced WMA workshop to convert my CD's to Wave files then I can convert them to MP3. I Convert to wave because when pushing 200+ watts out of a loudspeaker it sounds great, however MP3's rarely sound good over 150 watts they are compressed so we can fit them into our portable devices and stick tiny speakers in our ears. True wave files sound the best because they are a 1 to 1 conversion from either the CD or Album, Converting a MP3 to Wave does not work well either you are just adding gibberish to the cut off sine wave audio. MP3's cut the top of the Sine Wave and then close the gap thus making the file smaller there is more than just this but this is a close explanation.
Here is a quote:
Both WAVs and AIFFs are compatible with Windows, Macintosh, and Linux operating systems. The format takes into account some differences of the Intel CPU such as little-endian byte order. The RIFF format acts as a "wrapper" for various audio compression codecs.
Though a WAV file can hold compressed audio, the most common WAV format contains uncompressed audio in the linear pulse code modulation (LPCM) format. The standard audio file format for CDs, for example, is LPCM-encoded, containing two channels of 44,100 samples per second, 16 bits per sample. Since LPCM uses an uncompressed storage method which keeps all the samples of an audio track, professional users or audio experts may use the WAV format for maximum audio quality. WAV audio can also be edited and manipulated with relative ease using software. The WAV format supports compressed audio, using, on Windows, the Audio Compression Manager. Any ACM codec can be used to compress a WAV file. The user interface (UI) for Audio Compression Manager may be accessed through various programs that use it, including Sound Recorder in some versions of Windows.