AIFF - uncompressed format when copied from a CD takes up the most room (about 10 MB/minute of song) MP3 - mpeg layer 3 audio compression, usually about 10:1 reduction (about 1 MB/minute of song) AAC - advanced audio coding, "newest" audio format, even more compression than mp3 with less audible loss which you use will be all according to your ear. many people are fine with either 128 kbps AAC or MP3 files, personally i rip all my cds in AIFF format when using my desktop, and then have a separate library of 192 kbps AAC files for my ipod. the best thing to do would be to test a few different settings and see what quality level you want. sandor On Jan 3, 2004, at 11:10 PM, Kevin Willis wrote: > I just got my G4/400 about two weeks ago. I installed Jaguar on it > last night. It sure is beautiful. I have spent this evening playing > around with it and setting up my preferences. One question I have so > far...What are the different music formats in iTunes? There is AAC, > AIFF, and MP3. What are the differences? Is one better than the > other? Which should I use for ripping CD's? > > > Thanks, > > Kevin > > ----------