Microdrive

Microdrive (MD) is a brand name for a miniature, 1-inch hard disk designed to fit in a CompactFlash (CF) Type II slot. The release of similar drives by other makers has led to them often being referred to as 'microdrives'. However, 'microdrive' is not a genericized trademark[1] and manufacturers other than IBM up to 2003 and Hitachi after do not officially refer to these drives as Microdrives. Some other companies such as Sony have licensed the name and sell re-branded versions, others such as Seagate have their own designs which fit in the same form factor.


Front view of a Seagate brand Microdrive. This particular device was removed from an Apple iPod mini, and is intended only for embedded use.


Same Seagate device, however, rear view. Note the Apple Inc. logo on the lower left side of the label. See this image of an iPod mini with Microdrive intact.
These drives fit into any CompactFlash II slot; however, they may consume more power than flash memory (currents on the order of 190 mA, peak 310 mA, at 3.3 V) and therefore may not work in some low-power devices (e.g., handheld computers). Nevertheless, they have some benefits over flash memory in terms of the way data is stored and manipulated. Microdrives can store 8 GB or more, but must be formatted for a file system which supports this capacity, such as ext3 or NTFS or FAT32 which might not be supported by older CompactFlash hosts. To avoid this problem, the operating system may partition a drive so that each filesystem is smaller than 4GB.
As of 2011, Microdrives are viewed as obsolete, having been eclipsed by solid-state flash media in read/write performance, storage capacity, durability, physical size, and price.