A Concise Definition
Of A Hard Drive

Want to know the precise definition of a hard drive? Well, the venerable hard drive is a key computer component where information can be stored on both sides and is stored permanently. In this article, we'll explore the definition of a hard drive by looking at its history, major components, operating mechanism as well as external hard drives. Knowing a bit about hard drives is important so that you can make proper purchasing decisions.

1. History

First, some background on the hard disk. Reynold Johnson invented the first hard disk drive named IBM 350 in 1955. It was a single headed device which had a capacity of five million characters (megabytes). Of course, these days, PCs have hard drives with storage capacities of gigabytes.
 

2. Parts Of A Hard Drive

The main parts of a hard drive include the platters, head arm, chassis, and the head actuator.

• A platter is a circular shaped magnetic coated device made up of aluminum, glass and plastic on which data can be stored. A hard drive has a number of platters which rotates at a speed of about 7000 RPM. Both sides of the platter are coated with magnetic material to accommodate more data. The head moves over one of the platter when rotates.
   

• The head arm moves the read-write head to the desired part of the disk to read or write the information which is similar to that of a tape recorder.
   

• The chassis is a housing that protects the internal parts or hard disk drive of a computer from the external materials that are dangerous to the computer.
   

• An actuator is electronic equipment that helps in the motion of head arm with the help of a motor.
   

3. Operating Mechanism

The spacing between the disk surface and the read-write head is in the order of nanometers. This is because the internal parts of the drive and other component parts must be free from dust, smoke, etc.

There is no direct contact between the head and the disk, otherwise it may damage the disk surface. In order to avoid this there must be a small gap in between them. This is done by maintaining a sufficient pressure of air inside the hard drive. This helps the head to flow over the disk surface without any damage.
 

4. External Hard Drive

Another type of hard drive is an external hard drive that is placed outside the computer. This is helpful for computers that have no space inside the cabinet for installing extra hard drive. Internal parts of the computer can be protected by means of this and extra powering is required. A big advantage of this type of drive is that backup of data is easier. The hard disk size is 3.5" or 2.5" where the later has less capacity but power consumption is less and easy to move.
 

Conclusion

I hope this article has taught you the proper definition of a hard drive. Hard drives are the most important storage device of in a computer. Be sure you find a hard drive that is of good quality so that it prevents problems in your computing experience.