Another leading effort was the one of the Library of Congress with its Experimental Search System (ESS). The ESS was "one of the Library of Congress' first efforts to make selected cataloging and digital library resources available over the World Wide Web by means of a single, point-and-click interface. The interface consists of several search query pages (Basic, Advanced, Number, and a Browse screen) and several search results pages (an item list of brief displays and an item full display), together with brief help files which link directly from significant words on those pages. By exploiting the powerful synergies of hyperlinking and a relevancy-ranked search engine (InQuery from Sovereign Hill Software), we hope the ESS will provide a new and more intuitive way of searching the traditional OPAC (Online Public Access Catalog)." (excerpt from the website in 1998)
Another interesting - and totally different - initiative was the creation of the Internet Public Library (IPL) by the School of Information and Library Studies at the University of Michigan. The IPL went live in March 1995 as the first U.S. digital public library to serve the internet community, and to catalog websites and webpages. The librarians' task was to choose the best documents available on the web, and process them as library documents for them to be easily accessed from the IPL website, that acted as a portal. The IPL sections were: Reference, Exhibits, Magazines and Serials, Newspapers, Online Texts, and Web Searching. There were also Teen and Youth sections. All items were carefully selected, catalogued and described by the IPL staff. As an experimental library, IPL also listed the best internet projects that were run by librarians, in the section Especially for Librarians. Since then, students from the IPL Consortium, a consortium of colleges and universities with programs in information science, have worked on maintaining and developing the IPL as a public library for the web.
# Union catalogs
In 1999, the two main union catalogs were WorldCat, run by OCLC
(Online Computer Library Center), and RLIN (Research Library
Information Network), run by the Research Libraries Group
(RLG).
What exactly is a union catalog? The idea behind a union catalog is to earn time by avoiding the cataloging of the same document by many catalogers worldwide. When catalogers of a member library catalog a new document, they first search the union catalog. If the record is available, they import it into their own library catalog and add the local data. If the record is not available, they create it in their own library catalog and export it into the union catalog. The new record is immediately available to all catalogers of member libraries. Depending on their status, experience and quality of cataloging, member libraries can either import records only, or import and export records.
OCLC (Online Computer Library Center) was created in 1971 as a non-profit organization dedicated to furthering access to the world's information while reducing information costs. The OCLC Online Union Catalog - renamed WorldCat much later - began as the union catalog of the university libraries in the State of Ohio. Over the years, OCLC became a national and then worldwide library cooperative, and WorldCat the largest library catalog in the world. In early 1998, WorldCat had 38 million records in 400 languages - with transliteration for non-Roman languages) - and an annual increase of 2 million records. In 1998, 27,000 libraries in 65 countries were using OCLC services (paid subscription) to manage their collections and provide online reference services.
WorldCat has only accepted one bibliographic record per document, unlike RLIN (Research Library Information Network), launched by the Research Libraries Group (RLG) in 1980. RLIN accepted several records per document, with 88 million records in early 1998.
Members of RLG were mainly research and specialized libraries. RLIN was later renamed the RLG Union Catalog. Its free web version, RedLightGreen, was launched in fall 2003 as a beta version, and in spring 2004 as a full version. This was a major move, not only for library members, but for all internet users, who could also access it for free.
In 2005, WorldCat had 61 million bibliographic records in 400 languages, from 9,000 member libraries in 112 countries. In 2006, 73 million bibliographic records were linking to one billion documents available in these libraries.
In August 2006, WorldCat began to migrate to the web through the beta version of its new website worldcat.org. Member libraries now provided free access to their catalogs and electronic resources: books, audiobooks, abstracts and full- text articles, photos, music CDs and videos. RedLightGreen ended its service in November 2006, and RLG joined OCLC.