Data storage buying guide

There was a time when large amounts of data were difficult to move from computer to computer, or when one crashed hard drive could result in months of work being lost forever.

Now, whatever the data storage problem there seems to be a simple solution. Data from an entire computer can be backed up at the click of a button, while slideshow presentations can be carried around on a keyring. Specialist hard drives are also available to relieve computers creaking under the weight of a movie collection and for people who want to share data across a network.

The best data storage solution can be found by examining your budget, the amount of data you would like to store, how you will access it and taking a few moments to get to grips with the finer technical points.

Hard Drives

External hard drives can be split into four main categories

Desktop external hard drives: are most suitable for storing large amounts of data for the long term, when portability and easy access are not high priorities. With the largest of the hard drives on the market able to store a staggering 120 high definition (HD) movies, 1,500 games or countless photographs, one purchase could meet your data storage needs for years to come.

Portable external hard drives: are built for life on the go and can be stored in jacket pockets, bags or alongside laptops. While they can hold almost as much data as the biggest desktop external drives at the top end of the market, they tend to operate more slowly, but can still comfortably store music libraries and graphic-heavy presentations. As they do not generally require a power supply, portable drives offer a plug and play alternative.

Media player hard drives: bridge the gap between your computer and high definition (HD) television. Capable of holding vast amounts of data, these hard drives play movies and images on your television screen with an HDMI cable. The latest models can hold entire multimedia libraries and connect with other hard drives across a network.

Network hard drives: allow users of multiple computers to access data from a single source. A small business may use this functionality to store commonly used files in one place; while in the home, a network drive allows music to be shared across iTunes to every computer or digital media player. The largest of network hard drives on the market are capable of backing up data from multiple computers.

What to look for?

Capacity: The main selling point of a hard drive is its capacity, measured either in gigabytes (GB) or terabytes (TB). One terabyte is a thousand gigabytes. Generally, buying a hard drive with a larger capacity offers better value per gigabyte. Consider how much space you will need for your hard drive by adding up how much data you intend to store on it. If you are planning to back up an entire computer then you should buy a hard drive capable of holding all your data, and preferably more to ensure your purchase is futureproof. A typical family PC could be comfortably backed up onto a 160GB hard drive, but those working on design, multimedia or music projects may be best served by a 2TB unit to avoid running out of space.

Speed: Spindle speed dictates how quickly you can access data from your hard drive and is measured in revolutions per minute (rpm). A speed of 7,200rpm is more than adequate for everyday use, but if you edit a lot of videos or want to use your external hard drive for another data-hungry task like multi-track music production, then a device with a spindle speed of 10,000rpm will serve you better.

The speed at which you can transfer data is also dependent on interface, or how your drive connects to your computer. Make sure your hard drive uses an interface that is compatible with your PC before you make a purchase. USB 2.0 is normally a safe bet and can transfer data at 480mbps (megabits per second), but also works with devices which use the older and slower USB 1.1 format. The speeds provided by USB 2.0 should allow you to comfortably stream a movie from the external hard drive.

Less well-known alternatives include FireWire 800, which can transfer data at 800mbps, while the rarer eSATA ports can reach speeds of up to 3,000mbps - perfect for professional design, video and music use. Some drives and computers support more than one interface, so check to see that you are using the fastest one available to you. But be warned, the transfer speeds advertised by manufacturers can be ‘optimistic’ and are dependent on the performance of your computer.

Durability: Picking up the slack between moving data from a hard drive to a computer, buffer memory helps increase the speed of transfers by storing small amounts of data until it can be processed. This is particularly useful for streaming video content – particularly HD pictures – from a hard drive to a computer or a television.

Auto back up: The software which accompanies an external hard drive may feature an auto back-up program, protecting you from losing valuable downloads, essential reports or vital spreadsheets. A program like this can be set up to back up automatically on a schedule, or you can use it to create a copy of your external hard drive on the drive itself, another drive, your computer or a secure internet server.

Online storage: Some manufacturers offer free online storage with their hard drives, although it is normally only a limited amount of space, perhaps up to 2GB. This can be useful to store the most essential of data, or to keep handy documents like a CV or portfolio of design work in a place where you can access it any time. You can purchase more online space from the manufacturer should you feel the need, but portable USB memory sticks generally offer the same ‘access anywhere’ functionality without requiring an internet connection.

Warranty: While you can often expect a one-year warranty as standard in the event that anything unexpected goes wrong with your data storage device, some manufacturers offer longer term cover. Two years is not uncommon and a select few may offer up to a five-year warranty.

Portable USB memory sticks

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Memory sticks are basically pocket-sized hard drives and are ideal for transferring and storing relatively small amounts of data such as word processing documents and presentations.

Portable USB memory sticks can be attached to keyrings, but with capacities now approaching 64GB at the higher end of the market, these handy devices can still carry thousands of songs or multimedia-rich presentations.

Based around flash hard drives (which operate more slowly than disk-based hard drives but have no moving parts), these sticks are able to interface with any computer using built-in USB connectors. Some memory sticks are also equipped with encryption to help you avoid sensitive data falling into the wrong hands should you misplace your gadget.

CDs, DVDs & Blu-ray Discs

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CDs can be used to store relatively small amounts of data very easily. They are cheap, easy to access and popular for storing music, but are fairly fragile and unreliable. With a top recording speed of 52x and a capacity of 700MB, users can create their own albums to be played in stereos in a matter of minutes, or back up relatively small computer files like word processing documents and spreadsheets.

CD-R discs are suitable for permanently recording data, whereas CD-RW discs can be overwritten with fresh data multiple times.

DVD discs can store around seven times the amount of data that a CD can, albeit at a slightly higher price. Ideal for storing and sending large files such as complex animations or videos to friends, colleagues or prospective clients through the post, the speed at which DVD discs can be written varies from product to product. Like CDs, data can be written to DVD-R discs just once, but content on DVD-RW discs can be altered on multiple occasions.

Blu-ray discs are designed to succeed DVDs and can hold approximately six-times more data (that’s the same as 42 CDs). Blu-ray discs are most commonly used for high definition movies and programmes. The discs are more expensive to buy and Blu-ray players and writers are still relatively uncommon, so make sure your computer has the right hardware.

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