Though few photo collectors know it, it’s an easy lesson to learn.
There are four standard color photographic processes/prints: c-print (chromogentic), dye-transfer, Cibachrome and Polaroid. The popular significance attached to each process is the quality and durability of the images. Some have better images than others, and some images last longer than others. Brief summary is as follows:
chromogenic print (also known as c-print). The c-print is the normal, everyday color photograph. This includes the snapshots in your family album, wedding photos, 8×10 you had autographed by Willie Mays, etc etc. 99.9 percent of color photographs are c-types. C-print images are often nice, but have a tendency to fade and discolor. This makes the process not desirable in the fine arts and for display photos.
Polaroid: You know what Polaroids are; those small instant, self developing photos you aunt may have shot at the reunion picnic. Images can be nice, though often fade. One neat thing about Polaroids is that each photo is unique. With most photographic processes, many original copies of a single image can be made. Due to the unique self developing way the are made, there is only one of a particular Polaroid.
Dye-transfer: The Rolls Royce of color photographs. Have unsurpassed image quality and are the least likely to fade or discolor. Scarce on the market, this process has been used by famous artists and for museum displays.
Cibachrome: The BMW of color photographs. High quality images, though not quite as good as dye-transfer. Long lasting images, though not as long as dye-transfer. Cibachromes are often easily identified due to their often super duper glossy fronts and common jet black borders. Also known as Ilfachrome.