External Hard Drive Buying Guide

External hard drives have seen an exponential increase in popularity in the recent years; and why not, for they are indeed a very useful accessory, that can come handy for a number of purposes. The first one of these is of course, when you have too much of data to store on your computer's hard drive, and very less space. The safest and most convenient thing to do in such a situation would be to take all the data in an external hard drive, and keep it safe according to your own convenience. Another case where external hard drives can prove to be beneficial is when you have to transfer data amounting to tens to hundreds of gigabytes. Certainly, you would not go too far with flash drives, since they can only store so much in one go.


Although many might argue the need to invest in an external hard drive when you already have an internal one in your PC/laptop, the question here is not one of data capacity, but of convenience of access. True, internal hard drives have come of age and provide excellent transfer rates and increasing capacities depending on your need and budget, but the point here is that they still transfer data in the same way, i.e., without giving you the option of portability. You can't carry your computer everywhere you go, let alone access the data. Further, as mentioned earlier, flash drives only give a limited amount of data storage capacity, and this is where external hard drives score. Giving you the freedom of carrying your data anywhere with mammoth storage capacities amounting to terabytes (1000GB), they have replaced flash drives whenever large amounts of data need to be carried/stored.


Their functioning is really simple – you just need to plug them using a data cable into the USB port, and that's it! You can now transfer all kinds of data and carry it with you. Although a majority of the external hard drives today are 'plug and play' a couple might require you to install a driver. Further, all the latest computers now come with USB 2.0 ports (as against USB 1.1 in older computers) which facilitate faster data transfer. You can also run applications from an external drive, which is a big benefit to professionals like designers, programmers, etc.




There are generally two kinds of external hard drives:


  • Portable hard drives, or hard disk drives (HDD), are 2.5” in size, and come in a slimline casing, which also makes them easier to carry. They are the more fragile of the two, and one needs to be very careful while transporting them. They are USB powered, and thus, don't need an external power supply unit like an adapter.
  • Desktop hard drives, or solid state drives (SSD), are 3.5” in size, and come in a mounted enclosure, which might also have integrated fans to ensure the temperature of the drive stays under control. This also has a positive effect on the life of the device. Its main purpose is storage capacity, and not portability. A regular SSD might have over 500GB of data storage capacity. They are also faster than the portable hard drives, although also cost a lot more. They need an external power source, and are useful when there is a lot of data to be transferred, since the current is kept constant.




The capacity of your external hard disk drive completely depends on what kind of data you want to store. If it comprises only of MS Office files like documents, presentations, etc., an external hard disk with a capacity of 250 GB would suffice for a long time. However, if you would like to store media files like songs and movies, you are certainly better off buying something with a capacity of 1TB onwards to make sure that there is always ample space for you.


Extra features

Some external drives are meant to serve as a backup plan in case the regular storage fails. In this regard, there are a couple of extra features like file retrieval and automatic backup that can come as a valuable addition for a nominal price. A few even go the extra mile to provide biometric protection like finger scanner to ensure that only you can access the data, besides the regular password protection feature.



Speed of an external hard drive basically refers to how fast can it read and write files. Usually, most of the options today are either eSATA or USB 2.0. eSATA is faster than USB 2.0, but also needs an external power source, which is a challenge in case you want to access data from it on the go. Further, the speed of a hard drive is measured in rotations per minute (RPM). The higher the RPM, the better would be the data transfer speed.


Network-Attached Storage

If you have a business, or have access to multiple computers within a particular area, it's best to go for a network-attached storage device, or NAS. These are external hard drives having a very large capacity and can thus, automatically back up numerous computers at once. As expected, they cost more than the regular hard drives, but are totally worth it if you consider their utility.