Memory Cards

We are currently enjoying the flash memory era.Flash memory along with ARM processors(embedded processors in general) had brought 'computers' to the hand from desktop. Few of the prominent types of memory cards are detailed below:
1) SD cards
Developed by SD(Secure Digital) Card Association,mainly panasonic,sandisk and toshiba.
(Board members of the association are Canon Inc., Eastman Kodak Company, Hewlett Packard, Industrial Technology Research Institute, Infineon Technologies AG, Kingston Technology Company, Matsushita Electric Industrial Co., Ltd., Motorola Inc., NEC Corporation, Nokia Corporation, Power Digital Card Co., Ltd., Samsung Electronics Co., Ltd., SanDisk Corporation, Sharp Corporation, Socket Mobile, Inc. and Toshiba Corporation.)

Types:SD,miniSD,MicroSD,SDHC,miniSDHC,microSDHC.
SD card capacities range from 8 MB to 2 GB and from 4 GB to 32 GB for SDHC cards as of 2008.
2) Memory Stick From Sony/Sandisk
Types:Standard,PRO,DUO,PRO DUO,PRO-HG Duo,Micro(M2)
The original memory stick was available in sizes up to 128 MB, and a sub-version, Memory Stick Select allowed two banks of 128 MB selectable by a slider switch, essentially two cards squeezed into one. An 8 GB card was unveiled at the 2006 Consumer Electronics Show in Las Vegas and according to Sony, the Memory Stick PRO has a maximum potential size of 32 GB.

3) xD ( From Olympus, Fujifilm)
Types:Standard,Type M,Type H
xD cards are used in Olympus and Fujifilm digital cameras and Olympus digital voice recorders; Fujifilm also made an MP3 player (xD-MP3) that used the cards. As of 2006, xD cards are available in capacities of 16 MB (16 MiB), 32 MB, 64 MB, 128 MB, 256 MB, 512 MB, 1 GB (1 GiB), and 2 GB. xD cards have dimensions of 20 mm × 25 mm × 1.78 mm, and each weighs 2.8 grams.
4) MultiMediaCard from Siemens/Sandisk
Types:MMC,RS-MMC,MMCMobile,MMCPlus,MMCMicro
MMCs are currently available in sizes up to and including 4 GB with 8 GB models announced but not yet available. They are used in almost every context in which memory cards are used, like cellular phones, digital audio players, digital cameras and PDAs. Since the introduction of Secure Digital card and SDIO (Secure Digital Input/Output) slot few companies build MMC slots into their devices (an exception is some mobile devices like the Nokia 9300 communicator, where the smaller size of the MMC is a benefit), but the slightly thinner, pin-compatible MMCs can be used in almost any device that supports SD cards if the software/firmware on the devices support them.
Aside:CompactFlash from SanDisk is still used in Digital SLRs due to its high capacity
Also read :Solid State Drives