Originally Posted by
PTravel
Most of my music is 192kb. The music that I write, arrange and record is in AAC, Apple's lossless codec, at 320kb.
AAC is a lossy codec, and it's not Apple's. It's part of the MPEG-4 standard that is a successor to the MPEG-3 standard.
If you want lossless, use FLAC. But iTunes doesn't support it, of course. And it will greatly increase the size of your music collection on disk. People I know who use it say they can hear a pronounced difference between lossy and lossless encoding.