Compact Flash

The compact Flash is the original memory card, its dimensions are 42 mm x 36 mm x 3 mm. Compact Flash memories are physically larger than other kinds of memories and are extensively employed in all top-line DSLRs. They are available in volumes up to a maximum of 2GB. Miniature hard drives are also available that have approximately the same factor as the Compact Flash card and the capacities range from 340MB to 4GB. These Microdrives are priced at a similar rate to Compact Flash cards up to capacities of 1GB, however a 4GB microdrive is cheaper than a 2GB compact Flash card. For the most part, Compact Flash cards are cheaper than any other form of solid state memory device. The disk controller provided in the compact flash cards and microdivers make camera electronics undemanding.

Secure Digital: The secure digital memory cards are very small with dimensions of 24 mm x 36 mm x 2 mm. The in-built write protect switch in these memory cards prevent the accidental deletion of images and, they also have certain encryption capacities that are barely noticed by serious photographers.

Multimedia: The Multimedia cards are of the same size as Secure Digital cards but with fewer features. Also these cards do not support any form of encryption. These cards can be used with some Secure Digital Cameras; however, they are not completely compatible with secure digital cards.

Memory Sticks:
Memory Sticks are introduced by Sony and are compatible only with Sony Cameras.
The other kinds of memories are Smart media, which is thinner than CF and has no on-card memory controller and XD, smaller than Secure Digital, used by Fuji, Olympus and Toshiba.