The xD (eXtreme Digital) format was launched by Fujifilm and Olympus in 2002, and is promoted by the group at the official xD-Picture Card website ( http://www.xd-picture.com/). With a complete name of xD-Picture Card, this format was intended solely for use with The xD (eXtreme Digital) format was launched by Fujifilmdigital cameras, although it did find applications elsewhere. Fujifilm and Olympus were two of the biggest supporters of SmartMedia, and the launch of xD was a pretty good sign that the future of SmartMedia was limited.
Each xD card measures a mere 20mm by 25mm by 1.7mm, making them smaller in overall size than even SD and MMC cards. The maximum capacity of xD cards is expected to be 8 GB, but typical cards can be expected up to 1 GB in size. The read speeds of xD cards is up to 5 MB/s, while write speeds can be up to 3 MB/s, making them fast, but not the fastest. xD cards also operate on 3.3V, and are promoted not only for their minimal size, but for their low power consumption.