There are five main types of digital camera memory cards. The first is secure digital, or SD. It is the most common memory card type and found amongst all types of cameras. While SD memory cards may be common, they have a downside of usually only storing a maximum of 2 GB of memory. In newer digital cameras or camcorders, you will often find a type of SD memory card known as Secure Digital High Capacity, or SDHC. These are the same size of an SD memory card but can hold a lot more data, usually up to 32 GB. An SD memory card can be used in place of a SDHC but an SDHC cannot be used in the older cameras which take SD only.

If you have a Sony camera or other digital device, then you can use a memory stick or the Pro or Pro Duo versions of the memory card. For Olympus digital cameras, the memory stick is called xD Picture Card. There are various storage spaces available for the xD Picture Card. The smallest memory card that you will find (at least of memory cards which are currently available) is the MicroSD or MicroSDHC card. These are usually found in mobile phones or sometimes in small Olympus digital cameras, though you will need a special adapter to use it in place of the xD Picture Card. A MicroSD/SDHC memory card is small but it has limits in how much data can be stored.