Editing Library catalog (section)

== Online ==
{{Main|Online public access catalog}}
[[File:Dynix-Main-Menu-via-Telnet.jpg|thumb|right|[[Dynix (software)|Dynix]], an early but popular and long-lasting online catalog]]
[[File:Card Division of the Library of Congress 3c18631u original.jpg|thumb|upright=1.5|right|Card Division, United States [[Library of Congress]], 1910s or 1920s]]
Online cataloging, through such systems as the [[Dynix (software)|Dynix]] software<ref name=dynix>{{Cite journal | doi = 10.1108/eb047078| title = Dynix, automation and development at Napier Polytechnic| journal = Program: Electronic Library and Information Systems| volume = 25| issue = 2| pages = 91| year = 1991| last1 = Dunsire | first1 = G. | last2 = Pinder | first2 = C. }}</ref> developed in 1983 and used widely through the late 1990s,<ref name=systemsinstalled>[http://www.librarytechnology.org/lwc-ils-marketshare.pl?SID=20120527624877929 Automation Systems Installed] {{webarchive |url=https://web.archive.org/web/20160105001313/http://www.librarytechnology.org/lwc-ils-marketshare.pl?SID=20120527624877929 |date=January 5, 2016 }} Counting by Library organizations.</ref> has greatly enhanced the [[usability]] of catalogs, thanks to the rise of [[MARC standards]] (an [[acronym]] for MAchine Readable Cataloging) in the 1960s.<ref>{{cite journal | url=http://journal.code4lib.org/articles/5468 | title=MARC21 as Data: A Start | author=Coyle, Karen | journal=The Code4Lib Journal | date=2011-07-25 | issue=14 | access-date=2012-12-07  | archive-date=2019-05-23  | archive-url=https://web.archive.org/web/20190523003243/http://journal.code4lib.org/articles/5468 | url-status=live }}</ref>

Rules governing the creation of MARC catalog records include not only formal cataloging rules such as [[Anglo-American Cataloguing Rules]], second edition (AACR2),<ref>{{cite web|url=http://www.aacr2.org/|title=AACR2|website=www.aacr2.org|access-date=2012-12-07 |archive-date=2020-03-22 |archive-url=https://web.archive.org/web/20200322220823/http://www.aacr2.org/|url-status=live}}</ref> [[Resource Description and Access]] (RDA)<ref>{{cite web|url=http://access.rdatoolkit.org/ |title=RDA Toolkit |access-date=2015-06-22 |url-status=dead |archive-url=https://web.archive.org/web/20150716192234/http://access.rdatoolkit.org/ |archive-date=2015-07-16 }}</ref> but also rules specific to MARC, available from both the U.S. [[Library of Congress]] and from [[OCLC]], which builds and maintains [[WorldCat]].<ref name="WorldCat">{{cite web
 |url          = http://www.oclc.org/ca/en/worldcat/statistics/default.htm
 |title        = WorldCat facts and statistics
 |year         = 2011
 |publisher    = [[Online Computer Library Center]]
 |access-date  = November 6, 2011
 |archive-date = 2011-12-05 
 |archive-url  = https://web.archive.org/web/20111205010000/http://www.oclc.org/ca/en/worldcat/statistics/default.htm
 |url-status   = live
}}</ref>

MARC was originally used to automate the creation of physical catalog cards, but its use evolved into direct access to the MARC computer files during the search process.<ref name=Avram>{{cite book|last1=Avram|first1=Henriette D.|title=MARC, its history and implications|date=1975|publisher=Library of Congress|location=Washington D.C.|isbn=978-0844401768|pages=29–30|hdl=2027/mdp.39015034388556}}</ref>

[[Online public access catalog|OPACs]] have enhanced usability over traditional card formats because:<ref name=DESIDOC>{{cite journal|last1=Husain |first1=Rashid |last2=Ansari |first2=Mehtab Alam |title=From Card Catalogue to Web OPACs |journal=DESIDOC Bulletin of Information Technology |date=March 2006 |volume=26 |issue=2 |pages=41–47 |url=http://desidoc.drdo.gov.in/ojs/index.php/djlit/article/viewFile/3679/2091 |archive-url=https://web.archive.org/web/20160207093710/http://desidoc.drdo.gov.in/ojs/index.php/djlit/article/viewFile/3679/2091 |url-status=dead |archive-date=2016-02-07 |access-date=17 January 2016 |doi=10.14429/dbit.26.2.3679 |url-access=subscription }}</ref>
# The online catalog does not need to be sorted statically; the user can choose author, title, keyword, or systematic order dynamically.
# Most online catalogs allow searching for any word in a title or other field, increasing the ways to find a record.
# Many online catalogs allow links between several variants of an author's name. 
# The elimination of paper cards has made the information more accessible to many people with disabilities, such as the [[visually impaired]], [[wheelchair]] users, and those who suffer from [[Mold health issues|mold allergies]] or other paper- or building-related problems.
# Physical storage space is considerably reduced.
# Updates are significantly more efficient.