Editing Magnetic tape

{{short description|Medium used to store data in the form of magnetic fields}}
{{Use dmy dates|date=October 2024}}
[[File:magtape1.jpg|thumb|7-inch reel of ¼-inch-wide audio recording tape, typical of consumer use in the 1950s–70s.]]
'''Magnetic tape''' is a medium for [[magnetic storage]] made of a thin, magnetizable coating on a long, narrow strip of [[plastic film]]. It was developed in Germany in 1928, based on the earlier [[magnetic wire recording]] from Denmark. Devices that use magnetic tape can with relative ease record and play back audio, visual, and binary computer data. 

Magnetic tape revolutionized [[sound recording and reproduction]] and broadcasting. It allowed radio, which had always been broadcast live, to be recorded for later or repeated airing. Since the early 1950s, magnetic tape has been used with computers to store large quantities of data and is still used for backup purposes.

Magnetic tape begins to degrade after 10–20 years and therefore is not an ideal medium for long-term archival storage.<ref name=ScientificAmerican>{{Cite web|author=[[Pogue, David]]|title=Digitize Those Memory-Filled Cassettes before They Disintegrate|url=https://www.scientificamerican.com/article/digitize-those-memory-filled-cassettes-before-they-disintegrate/|url-status=live|language=en-US|website=[[Scientific American]]|date=1 September 2016|accessdate=26 July 2022|archivedate=19 August 2016|archiveurl=https://web.archive.org/web/20160819175937/https://www.scientificamerican.com/article/digitize-those-memory-filled-cassettes-before-they-disintegrate/}}</ref> The exception is data tape formats like [[Linear Tape-Open|LTO]] which are specifically designed for long-term archiving.<ref>{{Cite web |last=Coughlin |first=Tom |title=LTO Tape Capacity Shipments Up In 2022 |url=https://www.forbes.com/sites/tomcoughlin/2023/05/28/lto-tape-capacity-shipments-up-in-2022/ |access-date=2023-12-19 |website=Forbes |language=en}}</ref>

Information in magnetic tapes is often recorded in tracks which are narrow and long areas of information recorded magnetically onto the tape, which are separate from each other and often spaced apart from adjacent tracks. Tracks are often parallel to the length of the tape, in which case they are known as longitudinal tracks,<ref>{{cite book | url=https://books.google.com/books?id=7WrCSCqMk5gC&q=longitudinal+magnetic+recording+tape | title=Magnetic Recording: The First 100 Years | isbn=978-0-7803-4709-0 | last1=Daniel | first1=Eric D. | last2=Denis Mee | first2=C. | last3=Clark | first3=Mark H. | date=31 August 1998 | publisher=John Wiley & Sons }}</ref><ref>{{cite book | url=https://books.google.com/books?id=WOMTEQAAQBAJ&dq=longitudinal+magnetic+recording+tape&pg=PA155 | title=Audio and Video Systems | isbn=978-1-040-14797-9 | last1=Anand | first1=M. L. | date=18 October 2024 | publisher=CRC Press }}</ref> or diagonal relative to the length of the tape in [[helical scan]].<ref>{{cite book | url=https://books.google.com/books?id=PdruCAAAQBAJ&q=magnetic+tape+tracks+handbook | title=Magnetic Recording Handbook | isbn=978-94-010-9468-9 | author1=Camras | date=6 December 2012 | publisher=Springer }}</ref> There are also transverse scan and arcuate scanning, used in [[Quadruplex videotape]]. [[Azimuth recording]] is used to reduce or eliminate the spacing that exists between adjacent tracks.

== Durability ==
{{See also|Preservation of magnetic audiotape}}
While good for short-term use, magnetic tape is highly prone to disintegration. Depending on the environment, this process may begin after 10–20 years.<ref name=ScientificAmerican/>

Over time, magnetic tape made in the 1970s and 1980s can suffer from a type of deterioration called [[sticky-shed syndrome]]. It is caused by [[hydrolysis]] of the binder in the tape and can render the tape unusable.<ref>{{cite book |chapter-url=http://unesdoc.unesco.org/images/0011/001126/112676eo.pdf#page=29|access-date=12 December 2017|title=Memory of the World: Safeguarding the Documentary Heritage. A guide to Standards, Recommended Practices and Reference Literature Related to the Preservation of Documents of All Kinds |chapter=Magnetic Materials|publisher=UNESCO|id=CII.98/WS/4|year=1998}}</ref>

==Successors==
Since the introduction of magnetic tape, other technologies have been developed that can perform the same functions, and therefore, replace it. Such as for example, hard disk drives in computers replacing cassette tape readers such as the [[Atari Program Recorder]] and the [[Commodore Datasette]] for software,<ref>{{cite web | url=https://books.google.com/books?id=NbgDAAAAMBAJ&dq=cassette+tapes+atari&pg=PA76 | title=Popular Science | date=September 1983 }}</ref> CDs and MiniDiscs replacing cassette tapes for audio, and DVDs replacing VHS tapes. Despite this, technological innovation continues. {{as of|2014}} [[Sony]] and [[IBM]] continue to advance tape capacity.<ref name="Sony2014">{{cite web |url=http://www.sony.net/SonyInfo/News/Press/201404/14-044E/index.html |title=Sony develops magnetic-tape technology with the world's highest*1 areal recording density of 148 Gb/in2 |publisher=Sony Global |access-date=4 May 2014 |archive-url=https://web.archive.org/web/20140505022337/http://www.sony.net/SonyInfo/News/Press/201404/14-044E/index.html |archive-date=5 May 2014 |url-status=dead }}</ref>

==Uses==
===Audio===
[[File:Kaseta magnetofonowa ubt.jpeg|thumb|[[Compact Cassette]] ]]
{{Main|Audiotape}}
Magnetic tape was invented for recording sound by [[Fritz Pfleumer]] in 1928 in Germany.<ref>{{cite book | title = Magnetic Recording: The First 100 Years |author1=Eric D. Daniel |author2=C. Denis Mee |author3=Mark H. Clark | publisher = Wiley-IEEE | year = 1998 | isbn = 0-7803-4709-9 | url = https://books.google.com/books?id=7WrCSCqMk5gC&q=%22Fritz+Pfleumer%22+tape&pg=PA48 }}</ref>

Because of escalating political tensions and the outbreak of World War II, these developments in Germany were largely kept secret. Although the Allies knew from their monitoring of Nazi radio broadcasts that the Germans had some new form of recording technology, its nature was not discovered until the Allies acquired German recording equipment as they invaded Europe at the end of the war.<ref>{{Cite web|url=https://www.bbc.co.uk/programmes/p07dg3wm|title=BBC World Service – The Documentary Podcast, A History of Music and Technology: Sound Recording|date=18 June 2019 |publisher=BBC|language=en-GB|access-date=2019-07-01|archive-url=https://web.archive.org/web/20190701223615/https://www.bbc.co.uk/programmes/p07dg3wm|archive-date=1 July 2019|url-status=live}}</ref> It was only after the war that Americans, particularly [[Jack Mullin]], [[John Herbert Orr]], and [[Richard H. Ranger]], were able to bring this technology out of Germany and develop it into commercially viable formats. [[Bing Crosby]], an early adopter of the technology, made a large investment in the tape hardware manufacturer [[Ampex]].<ref name="Fenster">{{cite magazine |author=Fenster, J.M. |url=http://www.americanheritage.com/articles/magazine/it/1994/2/1994_2_52.shtml |title=How Bing Crosby Brought You Audiotape |magazine=Invention & Technology |date=Fall 1994 |archive-url=https://web.archive.org/web/20110404045940/http://www.americanheritage.com/articles/magazine/it/1994/2/1994_2_52.shtml |archive-date=4 April 2011 |url-status=dead}}</ref>

A wide variety of audiotape recorders and formats have been developed since. Some magnetic tape-based formats include:
* [[Reel-to-reel]]
* [[Fidelipac]]
* [[Stereo-Pak]] (Muntz Stereo-Pak, commonly known as the 4-track cartridge)
* [[Sound follower#Operation|Perforated (sprocketed) film audio magnetic tape (sepmag, perfotape, sound follower tape, magnetic film)]]
* [[8-track tape]]
* [[Compact Cassette]]
* [[Elcaset]]
* [[RCA tape cartridge]]
* [[Mini-Cassette]]
* [[Microcassette]]
* [[Picocassette]]
* [[NT (cassette)]]
* [[ProDigi]]
* [[Digital Audio Stationary Head]]
* [[Digital Audio Tape]]
* [[Digital Compact Cassette]]

=== Video ===
[[File:VHS head drum 2.jpg|thumb|A [[VHS]] helical scan head drum. Helical and transverse scans made it possible to increase the data bandwidth to the necessary point for recording video on tapes, and not just audio.]]
{{Main|Videotape}}
Videotape is magnetic tape used for storing video and usually [[Sound recording and reproduction|sound]] in addition. Information stored can be in the form of either an [[analog signal|analog]] or [[Digital signal (signal processing)|digital signal]]. Videotape is used in both [[video tape recorder]]s (VTRs) and, more commonly, [[videocassette recorder]]s (VCRs) and [[camcorder]]s. Videotapes have also been used for storing scientific or medical data, such as the data produced by an [[electrocardiogram]].

Some magnetic tape-based formats include:
{{div col|colwidth=16em}}
* [[Quadruplex videotape]]
* [[Ampex 2-inch helical VTR]]
* [[Type A videotape]]
* [[IVC videotape format]]
* [[Type B videotape]]
* [[Type C videotape]]
* [[EIAJ-1]]
* [[U-matic]]
* [[Video Cassette Recording]]
* [[Cartrivision]]
* [[VHS]]
** [[VHS-C]]
** [[S-VHS]]
*** [[Digital S]]
*** [[W-VHS]]
*** [[D-VHS]]
* [[Video 2000]]
* [[V-Cord]]
* [[VX (videocassette format)]]
* [[Betamax]]
* [[Compact Video Cassette]]
* [[Betacam]]
** [[Betacam SP]]
** [[Digital Betacam]]
** [[Betacam SX]]
*** [[MPEG IMX]]
** [[HDCAM]]
*** [[HDCAM SR]]
* [[M (videocassette format)]]
* [[MII (videocassette format)]]
** [[Multiple sub-Nyquist sampling encoding#UniHi|UniHi]]
* [[D-1 (Sony)]]
* [[DCT (videocassette format)]]
* [[D-2 (video)]]
* [[D-3 (video)]]
* [[D5 HD]]
* [[D6 HDTV VTR]]
* [[Video8]]
* [[Hi8]]
* [[Digital8]]
* [[DV (video format)|DV]]
** [[MiniDV]]
** [[DVCAM]]
*** [[DVCPRO]]
*** [[DVCPRO50]]
*** [[DV (video format)#DVCPRO Progressive|DVCPRO Progressive]]
*** [[DVCPRO HD]]
** [[HDV]]
* [[MicroMV]]
{{div col end}}

=== Computer data ===
[[File:Tapesticker.jpg|thumb|left|Small open reel of [[9-track tape]] ]]
{{Excerpt|Magnetic-tape data storage}}

== See also ==
* [[Analog recording]]
* [[Magnetic developer]]
* {{anl|Print-through}}
* [[List of magnetic tape cartridges and cassettes]]

== Notes ==
{{notelist}}

== References ==
{{reflist}}

== External links ==
{{Commons and category|Tape|Magnetic tapes}}

* [https://web.archive.org/web/20040603152849/http://www.tvhandbook.com/History/History_recording.htm History of Tape Recording Technology]
* [https://obsoletemedia.org/ The Museum of Obsolete Media]

{{Magnetic storage media}}
{{Music technology}}

{{Authority control}}

[[Category:Audiovisual introductions in 1928]]
[[Category:Audio storage]]
[[Category:Computer storage tape media]]
[[Category:Magnetic devices]]
[[Category:Sound recording]]
[[Category:Tape recording]]
[[Category:German inventions]]
[[Category:1928 in Germany]]
[[Category:1928 in science]]