Despite tough competition from flash drives, traditional mechanical hard disks are expected to continue leading the storage market for another few years.

Japanese company TDK recently showed off a flash-based hard drive with a storage capacity of 32GB. Despite its large size, TDK believes it is this type of storage device that is a threat to standard hard drives, but storage manufacturer Seagate disagrees.

Seagate believes that standard mechanical hard drives will continue to be the "undisputable king of storage when it comes to capacity and cost efficiency".

The company claims to have beaten the world record in cramming data into a hard drive: a massive 8.2GB of data per square centimetre has been squeezed into a hard drive.

1TB of data per square inch

Fujitsu takes the challenge even further. It claims its new heat-assisted recording method ( HARM ) technology will make it possible to cram 1TB of data per square inch, or 155GB per square centimetre.

Fujitsu's technology paves the way for 5TB hard drives: 10 times the capacity of modern 500GB drives, but smaller in size.

At a demo, Joel Hagberg, marketing and business development vice-president at Fujitsu, talked of the achievement as "an exciting milestone for high density recording development, as well as for the storage industry as a whole".

The technology that Seagate has developed builds on perpendicular storage on magnetic media that can be manufactured with its existing production equipment.

Seagate said its technology means we will get to see 1.8-inch hard drives (used in Apple iPods for example) with a storage capacity of 275GB, 2.5-inch hard drives with a 500GB capacity for notebook computers, and 3.5-inch drives for desktop computers and servers with storage capacities up to 2.5TB.

Seagate foresees these types of high capacity drives begining to enter the market during 2009. Further on in the future technologies such as heat-assisted magnetic recording, and new types of patterned media, will bring storage capacities to 970GB per square centimetre, or more.

Fujitsu said it will be three to five years before HARM technology disk drives become available. Perpendicular recording technology will deliver a 1TB capacity drive next year. Anna Lagerkvist