The microSD format was originally called T-Flash, and then TransFlash, before being renamed microSD when adopted by the SD Card Association (SDA). At 15 mm x 11 mm x 1.0 mm it is currently the smallest memory card format available. It is about one quarter of the size of a standard SD card but can be inserted into an adapter which allows the card to be used in devices with an SD card slot. TransFlash and microSD cards are essentially the same, and each can be used in devices made for the other type. There is one exception, which is that unlike TransFlash, microSD devices have the capability to support NFC (Near Field Communication).
These are all the same:
For a complete list of devices that use this memory : Click
TransFlash (Micro SD) Memory Card 32MB, 64MB, 128MB, 256MB, 512MB, 1GB, 2GB