Online Public Access Catalogue By Dr S L

Online Public Access Catalogue By Dr. S. L. Sangam Professor and Chairman Department of Library and Information Science Karnataka University, Dharwad

OPAC and Catalogue

Introduction v. OPAC stands for Online Public Access Catalogue v. It’s a way of finding books and other resources in the library

What is OPAC? v‘OPAC’ is an intelligent gateway to diverse integrated information resources for both the information specialist and the library patron or end user; gateway accessible not only in libraries, but at places of work, study, leisure and home. v. In fact it is a window to see the display of a library catalogue on a computer material user can search

cont Author Title Subject Key Call number Conference Title Boolean Conditions Others- series, subtitle, otherkey, uniform title Books on order It has link to the printer

Need The present day society is called paperless society where the information plays a vital role. The OPAC opens the way of effective and efficient resources sharing and it overcomes the inadequacies of the card catalogue. The deficiencies and the costs of maintaining the card catalogue require the change to this new form of catalogue. It has made the library files easily accessible to everyone by breaking the physical boundaries of the library itself

Origins of OPACs (cont'd) Computer-based library catalogs Initially used one or a very few special terminals to display results The terminals were located only in the library In most cases, the terminals were intended to be operated only by specially trained library staff

Origins of OPACs (cont'd) Computer-based library catalogs were initially restricted to small numbers of staff-operated terminals because, in the 1960 s and early 1970 s, Computers were rarely available to the general public Each computer network was served by a single computer Connections between networks—the inception of internetworking, and the Internet—were limited to a few experimental interconnections

Origins of OPACs (cont'd) By the mid-1970 s individual libraries, mostly at colleges and universities, began to develop computer-based catalogs open to their users, scil. , public-access catalogs (PACs) Pioneers in developing PACS included Northwestern University Library Widener Library, Harvard University Biblioteca Daniel Cosío Villegas, El Colegio de México

Origins of OPACs (cont'd) By the early 1980 s many libraries moved away from using card catalogs Typically, the shift to a computer-based catalog began with the closing of the card catalog to new cards as of a certain date After that certain date, all new materials added to the library's collection would be accessible only through the PAC

Origins of OPACs (cont'd) Most libraries also went through a process known as "retrospective conversion" In retrospective conversion, machine-readable cataloging records are acquired, or created locally, for older holdings These records are added to the PAC, and the corresponding catalog cards are destroyed, till eventually all or almost all reliance on printed cards for cataloging information ends

Origins of OPACs (cont'd) As the Internet developed in the 1980 s, many PACs were made accessible over the Internet via use of the Telnet protocol Thus, PACs became known as Online PACs or OPACs

Origins of OPACs (cont'd) With the explosive development of the World- Wide Web in the 1990 s, OPACs were rapidly made accessible via the Web (i. e. , via the Hyper. Text protocol) Telnet access for OPACs faded into past history Web-based OPACs are sometimes called Web. PACs

Examples of OPAC Capabilities As examples of OPAC capabilities that would be nearly impossible in a card catalog, consider some capabilities provided by UTNet. Cat at The University of Texas at Austin Keyword searches with limiters Number searches

Problems with OPACs Printed cards for library catalogs offered a few advantages over their computer-based successors In general, these advantages stemmed from the widespread use of a single source of printed cards: viz. , the Library of Congress working with the U. S. Government Printing Office

Problems with OPACs (cont'd) Schemes for transliterating from non-Roman alphabets differ from OPAC to OPAC, whereas printed Library of Congress catalog cards used a standard: viz. , LC's transliteration schemes

Problems with OPACs (cont'd) Alphabetization rules in OPACs are almost always based on the internal rules by which computers sort characters. These rules fail to take account of variations that occur within different languages. For example: In traditional library cataloging practice with printed cards, English names beginning with Mc or Mac (e. g. , Mac. Donald) were alphabetized separately, ahead of other names beginning with “M” In Spanish, "ch", "ll", and "ñ" are considered separate letters of the alphabet, but computer sorts ignore this distinction

Differences among OPACs One might think that it would be simple for libraries to agree upon a standard way of displaying the information in their OPACs and on a standard set of options available to users who want to search OPACs. Such a standard would be analogous to the standardization provided by the widespread use among libraries of catalog cards printed by the Library of Congress. In practice, efforts toward the goal of achieving such a standard have encountered numerous difficulties because of differences that have arisen over the years in the ways in which OPACs have developed In large part, each library has set up its own interface and made its own choices of data to be (1) stored in the database of its OPAC and (2) displayed in various screens offered to the end-users of its OPAC.

Advantages of OPACs It is easier to search and not boring any more Searing the OPAC is more a fun The User need not wake a way to search card catalogue drawers. OPAC display is easy to limit in the card catalogue when there were 100 cards under a subject, you have to go through all go of them. It enables a person to find a book of which the author, the title or the subject is known. The patron need not wander from one place to other to follow the see and see also references. Upgradation of catalogue can be done in short span of time

Advantages of OPACs (cont'd) In OPACs users can, in principle, perform other kinds of searches that are, as a practical matter, difficult or impossible in a card catalog: e. g. , Call number, publication date, location (in a multi- branch library), language, publisher, series, illustrator The actual capabilities for such searches vary according to individual implementations of OPACs in different libraries

Disadvantages of OPAC The equipment is currently expensive and beyond the means of many libraries. Some costs, such as hard copy printouts, may have to be charged to the patron Equipment failure or loss of power will mean no access to the collection via the catalogue There may be rush at CRT terminals at busy times where one waits in queue Catalogue user may need detailed assistance and training in using CRT terminals Library personnel will have to be retrained to use the online catalogue