Editing Digital permanence (section)

===Magnetic media===
[[File:magtape1.jpg|thumb|{{convert|7|in|cm|adj=on|0}} reel of {{convert|1/4|in|mm|0|adj=mid|wide}} audio recording tape, typical of consumer use in the 1950s–70s]]

[[Magnetic tape]]s consist of narrow bands of a magnetic medium bonded in paper or plastic. The magnetic medium passes across a semi-fixed head which reads or writes data. Typically, magnetic media has a maximum lifetime of about 50 years<ref name="Adelstein">Adelstein, Peter Z. "Permanence of Digital Information". Available at [http://www.ica.org/citra/citra.budapest.1999.eng/adelstein.rtf www.ica.org] {{Webarchive|url=https://web.archive.org/web/20040926035349/http://www.ica.org/citra/citra.budapest.1999.eng/adelstein.rtf |date=2004-09-26 }}.</ref> although this assumes optimal storage conditions; life expectancy can decrease rapidly depending on storage conditions and the resilience and reliability of hardware components.
* magnetic tape reels
* magnetic stripe cards
* magnetic cards
* [[compact audio cassette|cassette tapes]]
* [[video tape|video cassette tapes]]

Magnetic disks and drums include a rotating magnetic medium combined with a movable read/write head.
* [[floppy disk]]s
* [[zip drive]]s
* [[hard disk]]s and drums