Welcome to our second edition of "Your Storage Blog," a new feature here at BSN* where you ask storage-related questions that interest you, and in return you will have a chance to win a 1TB Seagate FreeAgent GoFlex portable drive for Mac or PC if your question is selected.

Our winning question is from Ed W., who asks: "How much more can consumers expect to see storage capacities increase for both desktop and laptop drives in the next 5 to 10 years and why?"

Great question Ed! To give you an insight into the answer, let me provide some background and a little technology history first.

Seagate Barracuda XT Drive with an open topTo increase storage capacity on a hard disk drive (HDD), we do this fundamentally by increasing areal density. Areal density can be thought of as how much information (or data bits) that can be put together on a disk platter. The idea is the smaller the data bits, and the more tightly packed they are together, the higher the overall areal density. Areal density on a HDD is measured and reported in bits per square inch. So for example, Seagate’s latest Barracuda XT 3TB drive features an areal density of 625 Gigabits per square inch and adds up to the drive providing one TB on each of its three platters.

There have been different recording processes used to increase areal density over time. Currently the industry is using perpendicular recording technology versus the previous technology called longitudinal recording. Each bit itself is designed to flip magnetically in one direction or another (think digital 0?s and 1?s).So a really easy way to visualize the difference is that longitudinal technology had its north/south bits or "poles" resting flat on the platters whereas perpendicular bits have its north/south poles facing upward vertically. In this way, you can see how perpendicular recording allows for a more tightly packed space for storing and retrieving information, and therefore greater increases in areal density can be achieved.

Another concept to understand when increasing areal density is the compound annual growth rate (CAGR). Typically, when a recording technology is first introduced, its CAGR starts out slow and then accelerates as understanding of the new technology is exploited. In the early part of this decade, CAGR was as high as 100%, but as the areal density increased, it became more challenging and the rates declined with a more recent average of around 40% industry wide. That may decrease some before we see the next technology surface, which for Seagate will be Heat Assisted Magnetic Recording (HAMR for short) in a few years.

Last year, I wrote a blog that covers this topic and explains some of these future storage technologies in more detail for Seagate here that you may be interested in checking out.

To get back to your original question, in general we’ve seen storage capacity of drives offered on the marketplace doubling every two years and we expect that to begin to slow to 25% or doubling every three years before it begins to accelerate again as new technology matures. In ten years’ time, if we were to build a desktop drive with three disk platters like the Barracuda XT, we might expect to see a capacity around 50TB. A laptop drive, with its smaller diameter platters, and the fact that they only use two of them per drive, could conceivably produce a drive capacity around 20TB.

Certainly not only is there continued demand for storage, but a great growth path for future hard disk drive technology development to meet those demands.

Thank you for your question Ed, and congratulations on winning your new SeagateFreeAgent GoFlex drive!
Readers – do you have a storage-related question you’d like to ask us at Seagate? We’ll be giving away at least two drives every month.

Visit the Seagate "Storage Means Business" blog landing page to submit your question and learn how you can win your own 1TB FreeAgent GoFlex portable drive. You can read the official rules here.

See you in a week (or so)!