The development of faster and more powerful computers has led to virtual flood of digital data. Over the decades capacity of data storage devices has continued to multiply. At the same time the dimensions of these digital silos have even become smaller. Year after year better devices and finer write-read-heads are developed. The magnetic bit domains became smaller and smaller. Until one day - they are no bigger than an atom. By using spin-polarized scanning tunnelling microscopy - a method of nanotechnology - it is possible today to determine the individual magnetic orientation of single atoms on surfaces, which means to read magnetic information atom by atom. If the same instrument could be used to write magnetic information in adjacent atoms, it would be possible to store the entire world literature on a space of a postage stamp. This is in the focus of research at the University of Hamburg.
