1) MP3 files are created by using MP3 ripper software to compress audio from music CDs into the MP3 format without loss of sound quality. 2) MP3 is an audio compression method that can compress CD quality audio into about 1/11 of its original size while maintaining average quality. It does this by removing inaudible data. 3) A compact disc (CD) is an optical disc used for storing digital audio. Standard CDs can hold up to 80 minutes of audio and have a diameter of 120mm.

1. Understanding MP3 Music File Work
groupE
*MP3 ripper
*MP3 Player
*CD
*Copyright Information

2. MP3 ripper
Application software to convert data into reading, a mp3 form from a
music CD.
That sound quality does not deteriorate at all unless read it, and
have damage to just handle digital data unlike recording is
characteristic.
As for the cause why a copy control CD was released, sound data done
ripping of in this ripping circulate through CD-R and the Internet
illegally, and that I gave a blow to the sales of the record maker is
assumed a reason of the copy control CD release.
It was it in a problem, but a lawful act of ripping software watches
an end in the form that there is no problem in by the reason of a
prevention of simple copying function sticking to a music CD for 1:00
period. Some ripping software is distributed as free software, and the
acquisition is easy.

3. What is MP3?
One of audio compression methods used with MPEG­1 of image data compression
method. One of audio
compression methods most widely widespread.
If volume of data can be compressed into about 1/11(128kbps) by using MP3 with the tone
quality of average music CD kept, and tone quality is sacrificed, a higher compressibility
can be obtained in MP3 according to Germany Fraunhofer IIS in the development origin
where the lossy compression method to obtain a high compressibility by thinning out the
data of the part that man doesn't feel easily as well as other main audio compression
methods is adopted.

4. CD(Compact Disk)
Compact Disc (or CD) is an optical disc used to store digital data, originally
developed for storing digital audio. The CD, available on the market since
late 1982, remains the standard playback medium for commercial audio
recordings to the present day.Standard CDs have a diameter of 120 mm and
can hold up to 80 minutes of audio. There are also 80 mm discs, sometimes
used for CD singles, which can store up to 24 minutes of audio.

5. Copyright Information
MP3 that includes copyright information cannot be used without permission. The
standard within the range of right protection is provided worldwide, but it differs
little by little according to the country.
One issue with MP3 files is that they can be considered a violation of an artist's
copyright. For example, if the file was created a violation of the artist's permission.
In some instances, an MP3 player won't play an MP3 file if someone who didn't get
the artist's permission ripped the file from CD. In other instances, the file will play,
but may contain copyright information about the MP3 file. However, in many
instances, the file can be played and does not include copyright information.

6. Reference
http://ja.wikipedia.org/wiki/%E3%82%B3%E3%83%B3%E3%83%91%E3%
82%AF%E3%83%88%E3%83%87%E3%82%A3%E3%82%B9%E3%82%
AF
http://e-words.jp/w/MP3.html
http://e-words.jp/w/E383AAE38383E38391E383BC.html
http://ja.wikipedia.org/wiki/%E8%91%97%E4%BD%9C%E6%A8%A9