Traditionally, drives extend the platters to as much of the width of the physical drive package as possible, to maximize the amount of storage they can pack into the drive. However, as discussed in the section on hard disk historical trends , the trend overall is towards smaller platters. There are several reasons why platters are shrinking, and they are primarily related to performance . Reducing the hard disk platter's diameter by a factor of two approximately quadruples its rigidity. Imperfect platters lead to low manufacturing yield and the potential for data loss due to the heads contacting uneven spots on the surface of a platter.
Smaller platters are easier to make than larger ones.
For performance reasons, hard disk spindles are increasing in speed. Smaller platters are easier to spin and require less-powerful motors. They are also faster to spin up to speed from a stopped position. Smaller drives generally use less power than larger ones. IBM's amazing Microdrive has a single platter and is designed to fit into digital cameras, personal organizers, and other small equipment.