MicroSD

                                          

microSD is a format for removable flash memory cards. The SD stands for Secure Digital. It is commonly used in cellular phones, but also in handheld GPS devices, portable media players, digital audio players, expandable USB flash memory drives, and for Nintendo DS flashcards, along with digital cameras.

It is the smallest memory card available commercially, with the lowest price per capacity and the higher capacity, as of 2008. At 15 mm × 11 mm × 1 mm (about the size of a fingernail), it is about a quarter the size of an SD card. There are adapters which allow a microSD card to be used in devices intended for SD, miniSD, Memory Stick Duo and even USB cards. However, they are not universally compatible.

TransFlash and microSD cards are the same (each can be used in devices made for the other), except that microSD adds support for SDIO mode, enabling non-memory cards like Bluetooth, GPS, and Near Field Communication devices.

A point of confusion can come from the difference in the microSD and the newer microSDHC format. The SD and SDHC share a similar form factor, but not all devices are compatible with the newer high capacity format. This is even true with devices that have been developed by SanDisk such as their e200 series of MP3 players. Using 3rd party firmware however, SDHC reading capabilities can be possible, but an external writer is still required

As of September 2008, microSD cards are available in capacities from 64 MB to 16 GB. A 12 GB version was developed by SanDisk but never released. Cards larger than 4 GB are only available in the newer SDHC format.

History

The microSD format was originally created by SanDisk. It was originally called T-Flash, and then TransFlash, before being rechristened microSD when adopted by the SD Card Association (SDA). Other flash card formats approved by the SDA include miniSD and SD.

The SDA announced the microSD format at CTIA Wireless 2005 on March 14, 2005, and approval of the final microSD specification was announced on July 13, 2005. At launch, the microSD format was available in capacities of 32, 64, and 128 MB. SanDisk introduced a 2 GB microSD card in July of 2006, initially priced at US$99.

Source : Wikipedia