Patterned media (also known as bit-patterned media or BPM) is a potential future hard disk drive technology to record data in magnetic islands (one bit per island), as opposed to current hard disk drive technology where each bit is stored in  within a continuous magnetic film. The islands would be patterned from a precursor magnetic film using nanolithography.
Structured storage may involve recording data on isolated magnetic islands rather than traditional methods that store bits in a single, unbroken magnetic strip. This new technology uses nanolithography to create the islands from an initial magnetic material.