Disk(s) - A Brief Overview

What does a hard drive do?
Storage is the hard drive's responsibility. Everything you keep on your computer is on a hard drive. Not just document, pictures, music and videos. Your programs, your preferences, even your operating system - they're all stored on your computer's hard drive. If your hard drive is damaged, you can lose it all. That's the sad story. Which is why most people have a backup system. They get another hard drive and copy all their important files onto that.

How big of a hard drive do you need?
Everything that can be saved on a hard drive is measured in terms of its size. Text is very small, pictures are larger, music is even bigger and video is the biggest of the bunch. A hard drive is like a scale. It doesn’t know the difference between things that are on it, it only knows their size. But instead of kilograms, a hard drive measures things in terms of megabytes (MB), gigabytes (GB) and terabytes (TB).

Roughly speaking a megabyte is 1 million bytes, a gigabyte is 1 billion bytes and a terabyte is 1 trillion bytes.

Will your drive work with a PC or a MAC?
Any drive works with either a PC or a MAC. Some drives are already formatted to work with one or the other. But any drive can be reformatted to work with either type of computer.

Note: if you reformat a drive, every single file on that drive is erased. So make sure you copy your files somewhere safe before you reformat.

It's more difficult to use the same drive on both a PC and a MAC. The short answer is they're not really compatible.

How important is hard drive speed?
When you start your computer, open a file, listen to a song, or do just about anything else, you use your hard drive. The discs inside the drive spin. The faster they spin, the more quickly your computer can find the file you want. So a drive rated at 7,200 rpm will be faster than one rated at 5,400 rpm. What that means for your day-to-day use will vary. With external drives, you'll hardly notice a difference. With internal drives, the difference will be slight with smaller files and applications, but will be obvious with larger files and applications.

4 main types of hard drives?

PATA - Parallel Advanced Technology Attachment
These types of drives are also known as Integrated Drive Electronics (IDE) and Enhanced Integrated Drive Electronics (EIDE) drives. The labels relate to the type of interface that is employed to connect the disk drive to the CPU board. These drives utilize either a 40 or a 80 wire cable with a broad 40-pin connectors. 40 wire cables are utilized in older and slower hard disks, whereas 80 wire cables are used in faster ones. Nowadays, these types of hard disks are being substituted by SATA hard disks. EIDE hard drives were introduced after some advancements in IDE hard disks, however, the term IDE refers to both IDE and EIDE disk drives.

Serial ATA (SATA)
These hard disks use a totally different connector than their PATA counterparts. Moreover, they also employ a different power adapter than IDE ones, though adapters are easily attainable. The main difference between a SATA and a PATA hard disk is that the former is thinner and purportedly have a faster data interface than the latter. Nevertheless, this speed dissimilarity is not distinguishable in PATA and SATA drives which have the same rpm rating. SATA drives are more efficient, and use less power than PATA ones.

SCSI - Small Computer System Interface
These hard disks are similar to IDE hard drives. They also spin at a higher rate in comparison to IDE and SATA ones. IDE and SATA drives generally spin at 7,200 rpm, whereas SCSI ones spin at 10,000 to 15,000 rpm. Today, SATA drives featuring a speed of 10,000 rpm are also manufactured. The higher the rpm, faster is the data access, but it may also lead to a faster breakdown. SCSI hard disks need a controller that operates the interface between the drives and the computer motherboard.

SSD - Solid State Drives
These hard disks, unlike the other types, don't consist of moving components. Typical hard drives comprise of a spinning magnetic disk that performs the function of data storage, but SSDs use semiconductors for this purpose. Since there are no moving components, these hard disks are much faster and less likely to break down than other drives. However, their price is a bit more than other hard drives.

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