This is the MP3 page.

MP3 stands for mpeg audio layer 3. It is a type of sound file that can compress CD quality music so the file is relly small. The compression ratio is arround 10:1. You can have higher compression ratios but, you won't get the CD quality sound.

MP3 Portables

MPMan was the first portable MP3 player.
Another popular MP3 portable is the Rio from Diamond Multimedia.
Samsung Electronics has a MP3 portable called Yepp.

MP3 Players

I think WinAmp is the best MP3 player out there. It isn't the best in decoding the file but, it is user friendly and it has plug-ins.
A good MP3 player is Nad. But its user interface isnt that good.
If you have win98 or IE 4.0 or better, you have a MP3 player built in. It is the active movie control. It is under the same secion where media player is under in the start menu. I do not recomend this one, because it uses allot of the CPU's power and the sound quality isn't as good as it could be.

MP3 Encoders

Audio Catalyst is a popular encoder from Xing.
CDex is a program that rips CDs and it Encodes also.
The people at Fraunhofer IIS created MP3 and they have an encoder.
Electronic Cosmo's MPEG Suite is a fast encoder.

Other

Napster is a file sharing/search engine for mp3. It is real good. some times I have seen more than a 2/3 TB to download.