An external hard drive works to expand three main functions of your computer. As opposed to an internal hard drive that is built into the computer, the external is bought separately to enhance what your computer can already do. A good drive works by allowing you more storage space, the ability to back up your data and to share this data with other computers. That’s why it is essential if you’re switching computers, as the external hard drive allows you to save this data and transport it to the new device. There are countless external hard drives to choose from, and which works best for you really depends on what you need to do, and what computer you already have.
Top 5 External Hard Drive
- Easily store and access 2TB to content on the go with the Seagate Portable Drive, a USB external...
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just...
- USB 3.0 and USB 2.0 Compatibility
- Fast data transfers
- Sleek profile design with a matte, smudge resistance finish
- Plug & play; Easy to use with no software to install. Requires reformatting for Mac OS v10.12 /OS X...
- Slim design
- Automatic backup - easy to use
- Fast data transfers
- High-capacity add-on storage
It’s a Great Time to Go for a Drive
In an era when Apple charges 99 cents per month for 50GB of iCloud storage and Google offers 100GB of free storage for two years with the purchase of a new Chromebook, mainstream external hard drives might appear less essential than they once were. But modern external drives are faster, more stylish, and often more durable than their counterparts from a few years ago. They’re ever cheaper and more capacious, too. For about $50, you can add a terabyte of extra storage to your laptop or desktop by just plugging in a USB cable.
The Need for Speed: Hard Drive or SSD?
Solid-state drives (SSD) have fewer moving parts than a traditional hard drive, and they offer the speediest access to your data. Unlike a conventional disk-based hard drive, which stores data on a spinning platter or platters accessed by a moving magnetic head, an SSD uses a collection of flash cells—similar to the ones that make up a computer’s RAM—to save data. (For an in-depth look at exactly how this cell-based storage works, check out this tech explainer from sister site ExtremeTech.)
Physical Size Matters: Desktop or Portable Drive?
If you have a large photo or video collection—perhaps you are a photo or video editor, or maybe a movie buff—you’ll likely need several terabytes of space in which to store it. So your best option is a desktop-class drive. We define these as having one or more spinning-platter drives inside and requiring its own dedicated power cable. Of course, in this scenario, your files are going to have to stay at your desk.
Need Redundancy or Extreme Speed? Consider a RAID
If you buy a larger desktop drive with two or more spinning platters, you’ll almost certainly have the ability to configure the drive as a RAID array using the included software. Depending on which RAID level you choose, you can prioritize capacity, speed, or data redundancy, or some combination thereof.
A collection of spinning drives configured with a RAID level designed for faster access can approximate the speeds of an SSD, while you should consider a drive with support for RAID levels 1, 5, or 10 if you’re storing really important data that you can’t afford to lose. Hit the link above for an explanation of the strengths of each RAID level.
Major Considerations before Purchase
There are a number of technical facts that can be considered when deciding on which external hard drive to buy. For the average person, there are basically five major considerations.
1) The Size of the Hard Drive or Hard Drive Capacity
This is the amount of space available for storage on the disk. A rule of thumb is to choose a hard drive about twice as large as the size of your computer’s internal hard drive. This will allow you to always have the available space for two backups of your computer if it needs to be restored. For other purposes such as external storage of working copies, your workload requirements will determine the size. It is always better to have too much external hard disk capacity than not enough because the latter would require you to purchase another hard drive.
2) The Data Transfer Rate
This is a technical number that basically tells you how fast the data will be transferred between the computer and the external hard drive. Slow data transfer rates are not always bad if you are in no hurry to copy or backup your data files. Users who need quick storage and retrieval times need to pay close attention to the data transfer rate.
3) The Type of Cable
The cable used to connect the computer to the external hard drive. Usually, the cable will come in the box with the hard drive. More importantly, check if the cable provided will support the maximum data transfer rate (above) of the device.
4) The Interface Between the Computer and External Hard Drive
This will be a cable, and the cable needs a connector on both ends. Your choice of the connector will directly affect your data transfer rate The main types of connectors are USB, Firewire, Thunderbolt, and eSATA. For most people, USB and Firewire are the most common choices since most computers have connectors already built into the unit. There are two versions of USB, 2.0 and 3.0, with 3.0 having a data transfer rate about twice that of 2.0.
This last consideration often ends up being the deal breaker. The external hard drives with the fastest data transfer rates and the greatest disk capacity are almost always the most expensive. Even if you do not have a requirement for terabytes of data storage, you may require the fastest data transfer speed. With the price, there is also the consideration of manufacturer and brand name, as some people are particular about buying from certain manufacturers.