<P> Tape remains a viable alternative to disk in some situations due to its lower cost per bit . This is a large advantage when dealing with large amounts of data . Though the areal density of tape is lower than for disk drives, the available surface area on a tape is far greater . The highest capacity tape media are generally on the same order as the largest available disk drives (about 5 TB in 2011). Tape has historically offered enough advantage in cost over disk storage to make it a viable product, particularly for backup, where media removability is necessary . </P> <P> Tape has the benefit of a comparatively long duration during which the media can be guaranteed to retain the data stored on the media . Fifteen (15) to thirty (30) years of archival data storage is cited by manufacturers of modern data tape such as Linear Tape - Open media . </P> <P> In 2002, Imation received a US $11.9 million grant from the U.S. National Institute of Standards and Technology for research into increasing the data capacity of magnetic tape . </P> <P> In 2014, Sony and IBM announced that they had been able to record 148 gigabits per square inch with magnetic tape media developed using a new vacuum thin - film forming technology able to form extremely fine crystal particles, allowing true tape capacity of 185 TB . </P>

When are the magnetic tapes used and how