A hard disk drive is the biggest component of warehouse in a computer. It is where all of the data in a computer, together with the operating system, applications and all user files (movies, music, photos etc) are permanently stored.
Over time, disk drives have evolved from being a few megabytes in size to over 1.5 terabytes. As is regularly the case with roughly all components of a computer system, this evolution has been accompanied with a steep decrease in price and a vast array of options to pick from.
Hard Drive
Some of the key characteristics to look for while researching hard drives include:
Size - this is regularly the most prominent factor while selecting a hard drive. Sizes range from 40Gb (gigabytes) to over 1.5 Tb (terabytes).
Disk speed - the speed of data passage is carefully by, among other things, the disk speed. The higher the speed, the faster data is transferred. Disk speeds are measured in Rpm (Revolutions Per Minute) and can range from 5400 - 12000 Rpm, with 5400 and 7200 being the commonly used speeds.
Internal/External - hard disk drives are whether encased in the computer (desktop/laptop) or they are used externally. At the very minimum, every computer has an internal hard drive that's used to store the operating system, applications and basic data. This drive can be augmented with an external, transported drive as well to increase warehouse capacity.
Interface - this determines how the hard drive connects to the computer. Internal hard drives roughly always have a Sata interface while external drives have more options for interfacing - Usb, FireWire and eSata (External Sata).
Given these parameters, the decision to buy a hard disk drive should always be evaluated from a usage standpoint: how is this drive going to be used?
For a computer that's primarily used for emailing/internet surfing and storing an mean number of data (photos, music, games etc), a basic, cheap, entry-level internal hard disk drive is more than sufficient. This would typically be something in the range of 120-140Gb with a disk speed of 5400 Rpm and a Sata interface. If, over time, warehouse needs increase, an external Usb/FireWire-based hard drive would be an perfect way to supplement existing drive space.
One striking aspect about hard disk drives is that prices have declined sharply over time, and continue to do so. Just in the past 5 years, the mean price per Gb has fallen from about .15/Gb to as low as .15/Gb. With prices so low, consumers don't have much motivation to buy a hard drive, with, say, a capacity of 40Gb, when they can spend a few extra dollars and get roughly quadruple that capacity.
Some of the popular manufacturers of hard drives include Seagate, Western Digital, Hitachi, Toshiba, Fujitsu etc. Each of these manufacturers has drives ready in every price segment and it's easy to find a cheap, trustworthy and high-quality drive.
Online retailers are an perfect place to start searching for deals on hard drives that are fine for every funds and requirement. When buying a hard drive, it's regularly cheaper to buy from a retailer than from the drive manufacturer. The same warranty is offered but with a significantly lower price and, frequently, with perks like free shipping.
A Guide to Buying the Right - And Cheap - Hard Disk Drive
