Chapter 9. Hard Disk Storage

Over the years, hard drives have been available in a number of physical formats, called form factors. These are normally based on the size of the platter used in the drive. Whereas desktop systems continue to use 3.5-inch drives, virtually all laptop/notebook systems use 2.5-inch drives, which were first introduced in 1988. There are also smaller form factors—all the way down to the 1-inch MicroDrive originally introduced in 1999. Except for the size of the disks and their packaging, the technology used in the 2.5-inch and smaller drives is the same as for the larger 3.5-inch models. This chapter covers hard drives, focusing primarily on the 2.5-inch and smaller drives that are used primarily in laptop/notebook or other portable systems.