Polymers show great potential as a durable and high density alternative for data storage and for this purpose the natural polymer DNA has already attracted much interest from researchers. A DNA based storage system, which makes use of the four nucleotides to store binary codes, is more durable and can store information with a much higher density than conventional storage systems. Synthetic polymers have properties that make them even more suitable for data storage, at least in principle, if complete control over their composition, i.e. monomer sequence can be obtained. This review addresses the current status of data storage in DNA, proteins, and synthetic polymers, with the objective to overcome the problems of the current data storage technology. Written records are crucial for our understanding of past civilizations. They are so important, that we commonly define "history" as the study of the past as it is described in written documents, and refer to earlier events as "prehistory". The main reason why we know so much about certain past civilizations is that they used durable media to store their writings and art. Thus we learned about old civilizations in Mesopotamia through 5,300-year-old clay tablets from Uruk that have been preserved until today, we learned about the late Shang dynasty (c. 1200-1050 BC) from China through inscriptions on oracle bones, and about the Olmec civilization in Mexico through the Cascajal Block, a stone slab with 3,000-year-old writing made of serpentinite 1. Digital data has completely changed the way we write, use, and access information nowadays and we live in what is commonly referred to as the 'digital world.' It is expected that the need for digital information will continue to grow, reaching the level of 44 trillion gigabytes in 2020 2-5. However, current data storage suffers from digital obsolescence: although the bits and bytes of the digital world are eternal, at least in principle, the storage devices are not. They deteriorate over time, usually within a few decades. For instance, memory cards and chips are maintainable for circa 10 years, while standard hard drives are susceptible to magnetic fields, high temperatures, and mechanical failures 6-8. The decay of the storage media results in data loss, which is currently prevented by a constant shuffling of data between different devices and facilities. Due to the explosion of digital data, there is a constant need to migrate to new technologies that do not always support the old technologies 9. Hence much of the information that we have stored on floppy disks, tapes, CD-ROMS, spinning hard drives and flash memory will soon be lost forever. And the challenges do not stop here. Current storage technologies require significant space and enormous amounts of energy 10. The world data centers currently consume annually ca. 420
