In the 1950's and 1960's the magnetic tape was widely spread as a common [?]. It's big advantage was that it could save amounts of data on relative small . But it had a big disadvantage. It had a reading procedure which needs a high . That meant that the data could only very slowly been read. This is called a access to data. Because of this modern data storage devices have a advantage over magnetic tapes. They also have a higher write density and function without the unpractical sequential access. But magnetic tapes are still used because of their high . Up to 1000 gb can be saved per tape. Another advantage that that they still have, is the high which can be written on a tape. In that they are similar to modern devices. But because of the access they have other problems. Although data can written on magnetic tapes times, the data can only be written on the of the tape. Other criteria of data storage devices are durability and to external influences. Although magnetic tapes are impervious to and collisions, they are vulnerable to moisture, dust, temperature and most importantly [?] which could harm the tape. But under good storage conditions and few [?] a viability of years is guaranteed without losing any quality. Another important point are costs. Compared to modern devices there is advantage. But the costs for the tape drives high. If there are huge amounts of data to save magnetic tapes are a good choice because of their low costs per bit compared to CD's/DVD's. Future developments are to improve the [?]. The [?] mainly depends on the consistency of the magnetic layer. That's why they seek to improve viability of the magnetic layer and the overall lifespan of magnetic tapes