How is data stored in a hard disk? Describe briefly.

Data is stored on magnetic platters inside the hard disk. A read/write head moves over the spinning platters, magnetizing tiny regions to represent binary data (0s and 1s).

Data in a hard disk drive (HDD) is stored magnetically on spinning disks called platters. Each platter is coated with a magnetic material. The hard disk uses read/write heads that float just above the platter surface. Here’s a brief breakdown of the process:

  1. Platters and Tracks: The platters are divided into circular tracks, and each track is divided further into sectors. These tracks form concentric circles around the center of the platter.

  2. Magnetic Encoding: Data is encoded as magnetic patterns (poles of opposite charges) on the platter’s surface. Each tiny area of the platter can hold a bit of data by switching its magnetic polarity, creating binary data (0s and 1s).

  3. Read/Write Heads: The read/write heads, which are mounted on an actuator arm, move over the platter to read data (by detecting the magnetic orientation) or write data (by changing the magnetic orientation of the area under the head).

  4. Spindle and Rotation: The platters spin at high speeds (typically 5,400 to 15,000 RPM), which allows the read/write heads to access different sections of the disk quickly.

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