The engineers at Fujitsu have managed a breakthrough which would allow the company to produce hard drives with 1Tb of data per square inch. This figure is almost seven times the density of the latest perpendicular recording drives. The technology behind this is referred to by Fujitsu as "patterned media" - it uses anodised aluminium to create a pattern of holes, each holding a portion of magnetic material used to store a single bit of data, with the aluminium oxide around each hole magnetically insulating it. Fujitsu is continuing to work on this technology, aiming for 4Tb per square inch by 2010.