Hard disk

Hard disk or Hard Drive (disk drive, HDD, “Winchester”) is a main storage device in most computers, based on the magnetic recording principle.

Looking on hard disk definition, it’s easy to see that in contrast to the “flexible” disk (floppy), in a case of hard disk the information is recorded on the “hard” materials. A single hard disk usually consists of several platters. Almost always, aluminum or glass plates are used. Each platter requires two read/write heads, one for each side.

Also (unlike a floppy disk or USB flash drive) the hard disk itself is usually combined with some other electronic devices, so it’s ready-to-use storage solution for computer users. Because of that hard drives are often used in non-removable computers.

Features

The hard disk has several basic characteristics:

  • Interface. The way of the interaction between 2 devices of different types. Modern hard drives can use ATA (IDE and PATA), SATA, eSATA, SCSI, SAS and other interfaces.
  • Capacity. The amount of data hard drive can store. Modern hard drives can store up to 5 TB.
  • Dimension. There are a lot of possible dimensions of hard drives: “classic” 8 and 5.25 inches, “standart” 3.5 or 2.5 inches and modern 1.8, 1.3, 1 and 0.85 inches.
  • Random access time. The average time the hard drive performs a read/write operations to a random section of the disc. Usual range of this parameter is from 2.5 to 16 ms (for comparison, this parameter for SSD-drives is less than 1 ms).
  • Energy consumption. The less energy consuming drive, the less you have to pay for its operating. Hard disk consumption for Mobile users directly affects the battery life.
  • Transfer Rate. The rate of data transmission. If this number is low, the speed of copying inside the disk and to an external media will be slow.


Learn more:

  • What Is Fixed Storage
    "Fixed storage is an internal media used by a computer to store data, and usually referred to as the Fixed Disks or Hard Drives. Fixed storage devices…"
  • Types and Examples of Compact Disc
    "A Compact Disc, commonly known as CD, is a polycarbonate disc with one or more metal layers capable of storing digital information. There are several primary…"
  • What is Smartmedia Card?
    "SmartMedia is a type of flash memory card that was mostly used in digital cameras and other portable electronic devices in the 1990s and early 2000s. SmartMedia…"


Backup Terms Glossary

Who uses Handy Backup?