There are various factors that have to be considered before you make a decision on which External drive to buy, let us have a look at these factors….
Storage Capacity
By far the most important consideration is the size of the External Hard Drive, the size you choose will depend on the amount of data you intend to store, for example if all you are storing is documents then you probably will not need a big drive, a small USB flash drive will suffice, if on the other hand you intend to store a lot of graphics, pictures, videos, music files, etc you would be better off choosing External drives with capacity in the ranges of 500GB to 2 Terabytes.
Security
The easiest and cheapest security can be implemented through the Computers operating system so if you are not too particular about protecting your files then you do not need to go for anything flashy, however there are various security options when it comes to External Hard drives:
1) Software: There are many Third Party Software programs that password protect your hard drive and encrypt the data as well – example is StorageCrypt 3, a lot of External Hard drives come with their own in built encryption and password protection capability
2) Fingerprint biometric access: Some Manufacturers have designed External Hard drives with built in biometric fingerprint access technology, an example of such a drive is the Aegis Bio which uses a fingerprint biometric sensor.
Data Transfer Speed
Speed may be an important factor for some users for example if you are capturing video you would probably need a faster data transfer rate due to the large size of the files as opposed to someone who is just transferring document files.There are two determinants of speed that have to be considered:
1)The data transfer rate of the Hard drive as specified by the Manufacturer, this is measured in Revolutions Per Minute (RPM), the higher the value the faster the device. 5400, 7200 or 10,000 RPM are the more common speeds available.
2) The interface used by the Hard drive to connect to and from Computers. Some of the common interfaces and their corresponding transfer speeds are:
USB 1.1 1.5 MB/s (Megabytes per second)
USB 2.0 60 MB/s
USB 3.0 625 MB/s
FireWire (IEEE 1394) 100 12.288 MB/s
FireWire (IEEE 1394) 200 24.576 MB/s
FireWire (IEEE 1394) 400 49.152 MB/s
FireWire (IEEE 1394b) 800 98.304 MB/s
FireWire (IEEE 1394b) 1600 196.6 MB/s
eSATA 3 GB/s
eSATA II 6 GB/s
Size and Durability
Some people prefer small and portable devices, and they do not come any smaller than a USB pen. USB pens although small and portable are limited in size having said that you can get USB pens of up to 256GB e.g. Kingston DataTraveler 310. There are larger and very sleek and portable models which are useful for those who want to copy a few files from one computer to another, there are also some very strong and durable models with tough protective cases or shock resistant rubber protectors to protect the device from accidental drops.
There are also available big and heavy devices that can store a large amount of data i.e Terabytes they are useful for users who want a dedicated data storage device to store there data and have no intention of carrying the device about.
External Hard drives are pretty useful devices used to protect and secure data, there are many types available on the market and you should take your time to choose one that meets with your requirements.
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