Computer hard drives store data magnetically.
Computers depend on quick access to immense stores of data. The movable heads in a modern hard drive make this speed possible by scanning the data wherever it may be on the disk, instead of reading the disk sequentially.
Definition
The Linux Information Project describes a disk drive as a storage device that can retain electronic data for long periods of time.
Parts
According to PC Guide, a typical movable head assembly for a computer's hard drive consists of tiny electromagnets, called heads, attached to an actuator arm positioned over a magnetic disk.
Operation
PC Guide explains that the heads write data onto the hard disk using electrical current, and read the data with magnetic fields. The actuator arm moves rapidly over the spinning disk to access the data.
Origins
According to the Magnetic Disk Heritage Center, IBM pioneered this data storage method with the RAMAC disk drive in 1956.
Modern Development
A Popular Mechanics article states that in 2007, magnetic disks could store 50 billion times more data than the 1956 RAMAC drive, and that Hitachi plans to use Giant Magnetoresistance (GMR) technology to bring subatomic storage to hard drives.
Tags: disk drive, hard drive, hard drives, Magnetic Disk
