Source: PCWorld
Hitachi’s new Deskstar 7K500 drive marks several milestones in the storage industry: It’s the first desktop hard drive to reach 500GB and one of the first to use the speedy new SATA II interface. In terms of how it stores data, though, the Deskstar may be among the last of its kind, as drive manufacturers begin to approach the limits of how densely they can pack data using today’s standard recording technology.
Demand for greater capacity continues to rise due in large part to a growing need for music and video storage on PCs and consumer electronics devices. To meet that need, storage vendors are turning to new recording technologies.
New Drive Technology: How it works
Hard drive makers, facing looming capacity limits with conventional, longitudinal recording technology, are turning to perpendicular recording to provide even greater storage.
**Conventional (Longitudinal) Recording
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Each bit of information is represented by a collection of magnetized particles, with their north and south poles oriented in one direction or the other. In longitudinal recording, the particles’ north and south poles are lined up parallel to the disk’s surface in a ring around its center. Magnetic repulsion limits how closely packed those bits can be and still maintain data integrity.
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Perpendicular Recording

**In this type of recording, the poles are arranged perpendicular to the disk’s surface, which allows more bits to be packed onto a disk and reduces problems from magnetic interference.
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