How Is Information Stored on Your Computer Hard Drive?

A hard drive is made of many platters that data are written on.

Hard drives provide data storage for your computer. When downloading files or saving a document, the information is written to the hard drive. Many computer owners install their own hard drive at some point, but few have seen the inside of one.

Platters

The physical part data are stored on, inside the hard drive, are the platters. These platters are many thin discs stacked on top of each other. The platters are given a magnetic coating. Data are encoded in ones and zeros, with magnetized spots representing the ones. The ones and zeros are called "binary," a code that computers understand at the mechanical level.

Heads

For each platter, there is a pair of heads, one for the top and the other for the bottom. These heads read and write data to the platter. They float just above the platters, with a cushion of air. This space is not, however, visible to the human eye. Even a speck of dust is capable of causing the heads to malfunction.

Interfaces

How the hard drive physically connects to the motherboard is via an interface. Common interfaces are Serial Advanced Technology Attachment (SATA), Parallel Advanced Technology Attachment (PATA), and Small Computer System Interface (SCSI). A small circuit board on the drive interprets data and moves it through the data cable attached to the pins at the back of your drive.

References

• Google Books | Mike Meyers' CompTIA A+ Guide