WHAT IS HARD DISC DRIVE (HDD)

Definition of a Hard Disc Drive

 

 You may have experienced this scenario: you turn on your computer and you get a black screen with the message 'Imminent Hard Disk Failure.' Or, you've dropped your laptop on the floor, your screen goes black, and your computer won't turn back on again. More often than not, the problem is your hard drive. If your hard drive has crashed, you may have lost all your documents, photos, music, etc. It can be one of the more frustrating experiences for any computer user. Read on to learn how your hard drive works and some simple steps you can take to avoid losing all your files if it crashes. 

A hard disk drive (HDD) is a non-volatile computer storage device containing magnetic disks or platters rotating at high speeds. It is a secondary storage device used to store data permanently, random access memory (RAM) being the primary memory device. Non-volatile means data is retained when the computer is turned off. 

Hard drives need a read only memory (ROM) controller board to instruct the read/write heads how, when and where to move across the platters. Hard drives have disks stacked together and spin in unison. The read/write heads are controlled by an actuator, which magnetically reads from and writes to the platters. The read/write heads float on a film of air above the platters. Both sides of the platters are used to store data. Each side or surface of one disk is called a head, with each one divided into sectors and tracks. 

How is a hard drive connected to a computer?

 

An internal hard drive is connected to the computer using a data cable (IDE, SATA, or SCSI) that connects to the motherboard and a power cable that connects to the power supply.

 Where is the hard drive found in a computer?

All primary computer hard drives are found inside a computer case and are attached to the computer motherboard using an ATA, SCSI, or SATA cable. Hard drives are powered by a connection to the PSU (power supply unit).

Note: Some portable and desktop computers may have newer flash drives that connect directly to the PCIe interface or another interface and not use a cable.

Hard Disk Drive Troubleshooting 

 

The hard drive in your computer is used over and over, each time you're doing something that involves reading or writing data to the disk. It's normal, then, to eventually run into a problem with the device.

One of the most common issues is a hard drive that's making noise, and the best first step in troubleshooting a hard drive malfunction of any kind is to run a hard drive test

  BIRTH OF HARD DISC DRIVE 

RAMAC

 

 IBM made the first commercial hard disk drive-based computer and called it RAMAC – short for “Random Access Method of Accounting And Control.” Its storage system was called the IBM 350. RAMAC was big – it required an entire room to operate. The hard disk drive storage system alone was about the size of two refrigerators. Inside were stacked 50 24-inch platters.
For that, RAMAC customers ended up with less than 5 MB – that’s right, megabytes of storage. IBM’s marketing people didn’t want to make RAMAC store any more data than that. They had no idea how to convince customers they’d need more storage than that.
IBM customers forked over $3,200 for the privilege of accessing and storing that information. A MONTH. (IBM leased its systems.) That’s equivalent to almost $28,000 per month in 2016.
Sixty years ago, data storage cost $640 per megabyte, per month. At IBM’s 1956 rates for storage, a new iPhone 7 would cost you about $20.5 million a month. RAMAC was a lot harder to stick in your pocket, too.

IMPORTANT HARD DISC QUALITY

 

Space: Obviously, storage space is important! Take a look at available specs for computers today, and you’ll see storage options up to 1TB and frequently beyond. SSDs were particularly important for hard drive storage, because they can store data in a much smaller space than HDDs. That’s why we have phones that can hold all our favorite music playlists.

Speed: The speed of a hard drive depends on how fast data can be read or written, as well as the type of connection the hard drive has to the rest of the computer, and how much data it can carry. HDDs were once rated by rpms/revolutions per minute, but SSDs are much faster and don’t need to spin anything.

Physical security: Physical security is usually about durability — whether your hard drive is tucked away inside a computer or an external version you carry around, it needs to be able to resist bumps and jostles, as well as heat and other environmental issues. More advanced hard drives may also have features that help discourage theft.

Connections: A hard drive may be connected by USB, SATA, eSATA, PCIe, and other connection options. This affects both speed and what the hard drive is compatible with or how easy it is to upgrade. Always watch connections when buying or upgrading!

Formatting: Hard drives may be formatted to work with particular operating systems or for other precise purposes. Typically you can reformat a hard drive to fit your own needs, but it’s a good idea to check how the hard drive has been formatted if you are making a purchase decision.