An External Hard Drive is a memory device which is used to store large quantities of information in excess of the computer's hard disk
. The information can be uploaded or downloaded into the device by using a USB cable which is usually a quick process unless the system configuration is low. External hard drives are an addition to the computer's existing memory making them critical when large amounts of data is to be stored.
These portable external hard drives have storage capacities ranging from 160GB to 4TB which is more than the memory capacity of some of the modern CPU's, though there are few drives which have much lower memory space and are mostly used for their portability. The 320GB External Hard Drive provides space equivalent to some of the higher end laptops. Though the drive is used for transfer of information, its high memory space makes it useful more as an additional storage device since laptops and few versions of computers have low storage capacity. Most the 320GB External Hard Drive can store all the information on your PC or laptop and hence be a backup in case the computer memory crashes.
The price of an external hard drive purely depends on the number of GB, each GB costing between 0.16 to 0.38 USD depending on several factors. Hence the low end 320GB External Hard Drive would cost around 50 USD. The 320 GB drive is capable of storing about 80,000 mp3 files or about 320 hours of DV video and hence is a great option for those who travel on business purposes or want to plan a world tour and capture all those beautiful memories. It is definitely a device which comes into the must category of buy rather than the 'want'.