A standard for storing 35mm photos in digital format on a CD-ROM. The PhotoCD is normally created at the same time as the photographic film is developed by digitising each frame at a resolution of 2,048 x 3,072 pixels with 24-bit colour (together with a lower resolution preview image file). One PhotoCD can hold 100 photographs. To read a PhotoCD disc, the CD-ROM drive must conform to theCD-ROM XA standard. If all the images are recorded on the PhotoCD at the same time, then the disc can be read by a single-session drive. If further images are recorded at a later date, then the disc can only be read by a multi-session CD-ROM drive.
If you want to display photographs on your PC, the simplest and cheapest way is to use the PhotoCD system. Take photographs with a normal colour film and ask for a PhotoCD disc when you take the film in to the chemist. A few days later, you should receive your pictures as normal together with a CD-ROM which has graphic files of the pictures and can be accessed from your CD-ROM drive.