What is the difference in a 2 eye and 6 eye record

6 eye is an earlier pressing and, usually, superior. The last were pressed in 1962 when the change to 2 eye was made. Original 2 eye pressings tend to be excellent. If you have the choice of a 6 eye or a 2 eye of the same title go for the 6 eye.

Thanks for the info, I just bought a "Kind of Blue", M Davis 6 eye. In the mail:O)

If you want to get really fancy you can look for six-eye monos and six-eye stereos. red label with black eyes on the monos, inverted on the stereos. I'll second Narrod that the two-eyes are hit and miss and the later no-eyes and everything else are very hit and miss from a quality perspective. Its unfortunate too, because Columbia's recording facilities delivered some really great sounding records - Kind of Blue, Time Out, etc.