Aunion catalog is a combinedlibrary catalog describing the collections of a number oflibraries. Union catalogs have been created in a range of media, includingbook format,microform,cards and more recently, networked electronicdatabases. Print union catalogs are typically arranged by title, author or subject (often employing acontrolled vocabulary); electronic versions typically support keyword andBoolean queries. Union catalogs are useful tolibrarians, as they assist in locating and requesting materials from other libraries throughinterlibrary loan service. They also allow researchers to search through collections to which they would not otherwise have access, such asmanuscript collections.
The largest union catalog ever printed is the AmericanNational Union Catalog Pre-1956 Imprints (NUC), completed in 1981.[1] This achievement has since been superseded by the creation of union catalogs in the form of electronic databases, of which the largest isOCLC'sWorldCat.[2] Other examples includeK10plus in Germany,Library Hub Discover (formerlyCOPAC) provided byResearch Libraries UK and AMICUS, provided byLibrary and Archives Canada.[3]
For academic publications, severalacademic search engines exist to combine theopen data provided byopen archives throughOAI-PMH, as well as records from publishers deposited inCrossRef and other sources. They includeBASE,CORE and Unpaywall, which indexes over 20 millionopen access publications as of 2020.[4]
The idea of sharing catalogue records among libraries is at least as old as theFrench Revolution, when a cataloguing standard was published encouraging librarians throughout France to contribute to cataloguing the nation's books by writing records on the backs ofplaying cards and mailing them off to the home of thenational library in Paris.[5]: 30–31 The idea was thus common knowledge among librarians throughout the 19th century. Nonetheless, it was not until 1901 that the U.S. Library of Congress exchanged cards with the Boston Public Library, Harvard College Library, and the New York Public Library[5]: 194 and also began a card publishing service to sell copies of its own catalog cards to public libraries throughout the U.S.[5]: 138–193 Card catalogues grew huge during the next six decades. In the late 1960s, the development ofmachine-readable cataloguing incomputerized andprogrammable form via theMARC standards meant that union cataloguing from then onward could be done electronically instead of physically.
| International | |
|---|---|
| National | |
| Other | |
.svg){kind=icon} | This article relating tolibrary science orinformation science is astub. You can help Wikipedia byexpanding it. |
