What is HDD (hard disk drive)

What is HDD ?

HDD↣ Hard Disk Drive

"HDD is a data/information storage device. For storing data/information it uses magnetic storage. To do this it uses one or more rigid rapidly rotating disk(platters) coated with magnetic material."

HDDs are type of non-volatile storage, retaining stored Data even when powered off.

HDDs are introduced by IBM in 1956. It is known as Secondary Storage Memory. It is also known as Permanent Memory.

Parts of HDD

There are many electrical and mechanical parts in Hard Disk Drive.

Platters are moving part of HDD, They rotate at very high speed. The platters inside are made of Aluminium or Glass or Plastic or Cerium material for light weight and strength.Different magnetic materials are coated on the platter with Phosphorous, Chromium, Cobalt-Chromium-titanium carbon based polymer. Data is written on the platters using this magnetic property.

Types of HDD:

1) IDE(Integrated Drive Electronics)/PATA(Parallel Advance Technology Attachment) Hard Disk »»

IDE/PATA

IDE↣ Integrated Drive Electronics

PATA↣ Parallel Advance Technology Attachment

This type of Hard Disk connects to the IDE connector Pin on the top of the computer motherboard using a 40 pin data cable.
From invention to upto now we can find IDE/PATA Hard Disk found in various storage size, from 10 MB to 750 GB models in market. But now IDE/PATA Hard Disk no more in use.

2) SATA(Serial ATA-Serial Integrated Drive Electronics) Hard Drive »»

SATA

SATA↣ Serial ATA-Serial Integrated Drive Electronics

In this type of Hard Disk, a seven pin serial type data cable connects to the SATA connector pin on the computer motherboard. Technology of SATA-l, SATA-ll, SATA-lll has evolved. in all the new amendments, a lot of attention was paid to increasing the speed of data transfer.

Sr. No.	SATA Revision #No	Data Bandwidth
1.	SATA l (Revision 1.x)	150 MB/Second
2.	SATA ll (Revision 2.x)	300 MB/Second
3.	SATA lll (Revision 3.x)	600 MB/Second

SATA Connections Type & Backward Campatibility :

You can also istall SATA-ll type of connection technology to hard disk of SATA-l connection technology.
You can also istall SATA-lll type of connection technology to hard disk of SATA-l and SATA-ll connection technology.

SATA Hard Disk Model &Storage Capacity:

3.5' Factor	2.5' Factor
SATA PC Hard Disk	SATA Laptop Hard Disk

SATA Hard Disk is available in 16GB, 32GB, 64GB, 128GB, 256GB, 500GB, 1TB, 1.5TB, 2TB, 4TB, 6TB, 8TB, 12TB.