Resources & Guides

Essential Library Terminology Every Librarian Should Know

Comprehensive glossary of essential library terms, acronyms, and jargon that every librarian and library professional should know.

10 min read

Whether you’re a new librarian, library assistant, or just want to refresh your knowledge, understanding library terminology is essential for professional communication and effective library operations. This comprehensive glossary covers the most important terms across all areas of library work.

Quick Navigation

General Library Terms

Accession

The process of formally adding a new item to the library’s collection, including assigning an accession number and creating a permanent record.

Archive

A collection of historical documents, records, or materials preserved for their long-term research value.

Branch Library

A library location that is part of a larger library system but operates in a separate physical location.

Consortium

A group of libraries that cooperate and share resources, often including shared catalogs, interlibrary loan, and purchasing agreements.

Deaccession (Weeding)

The process of removing materials from a library collection, typically because they are outdated, damaged, or no longer relevant.

Special Collections

Rare, valuable, or unique materials that require special handling and restricted access, such as manuscripts, rare books, or archival materials.

Stack

The area where library materials are shelved for storage and browsing.

Cataloging & Classification

Authority Control

The process of maintaining consistent forms of names, subjects, and other access points in bibliographic records.

Authority Record

A record that establishes the authorized form of a name, subject, or series title, with references from variant forms.

Bibliographic Record

A catalog entry that describes a library item, including author, title, publisher, physical description, subject headings, and classification number.

Call Number

A unique identifier assigned to library materials that indicates their location on the shelf. Typically combines classification number + author/title designator + publication year.

Copy Cataloging

The practice of adapting an existing bibliographic record from another library or database rather than creating an original record.

DDC (Dewey Decimal Classification)

A library classification system that organizes materials by subject using a numeric code from 000-999. Most widely used in public and school libraries worldwide.

Item Record

The record for a specific physical or electronic copy of a work, including barcode, location, and circulation status.

LCC (Library of Congress Classification)

An alphanumeric classification system used primarily by academic and research libraries in North America.

MARC (Machine-Readable Cataloging)

The international standard format for bibliographic data, allowing catalog records to be read and processed by computers.

MARC21

The current version of the MARC format used in North America and many other countries.

Metadata

Structured information that describes, explains, locates, or otherwise makes it easier to retrieve, use, or manage information resources.

Original Cataloging

Creating a completely new bibliographic record for an item that has no existing record in shared databases.

Subject Heading

A standardized term or phrase used to describe the content or topic of a library item, enabling users to find materials on specific subjects.

UNIMARC

The universal MARC format used internationally, particularly in Europe.

Circulation

Check In

The process of recording the return of a library item and updating its availability status.

Check Out

The process of lending a library item to a patron and recording the transaction.

Circulation Period (Loan Period)

The length of time a patron is allowed to borrow an item before it must be returned.

Claims Returned

A status indicating a patron claims to have returned an item that the library cannot locate.

Fine

A monetary penalty charged to patrons for overdue items, lost materials, or other policy violations.

Hold (Reserve)

A request placed by a patron to borrow an item that is currently checked out or located at another branch.

ILL (Interlibrary Loan)

A service that allows patrons to borrow materials from other libraries when their home library doesn’t own the item.

In Transit

Status indicating an item is being transferred between library locations.

Lost

Status indicating an item has been declared lost, either by a patron or through library inventory.

Overdue

Items not returned by the due date.

Patron

A registered user of library services (also called member, borrower, or cardholder).

Recall

A request to return a checked-out item earlier than the original due date, typically to fulfill another patron’s urgent need.

Renewal

Extending the loan period for a checked-out item.

Reserve (Course Reserve)

Materials set aside for a specific class or instructor, often with shortened loan periods.

Transit

The process of physically moving items between library locations.

Collection Development

Acquisition

The process of obtaining materials for the library collection through purchase, gift, or exchange.

Approval Plan

An arrangement with a vendor to automatically supply books matching specific subject criteria.

Budget Allocation

The distribution of library funds across different subject areas, formats, or departments.

Collection Policy

A formal document outlining the library’s approach to building, maintaining, and weeding its collection.

EDI (Electronic Data Interchange)

Automated exchange of ordering and invoicing data between libraries and vendors.

Invoice

A bill from a vendor for materials purchased or services provided.

Purchase Order (PO)

An official document authorizing the purchase of materials from a vendor.

Selector

A librarian responsible for choosing materials to add to the collection in specific subject areas.

Serials

Publications issued in successive parts, such as journals, magazines, and newspapers.

Standing Order

An arrangement with a vendor to automatically supply all publications in a specific series or category.

Vendor

A company that supplies books, journals, or other library materials.

Digital Libraries & Technology

API (Application Programming Interface)

A set of protocols that allows different software applications to communicate with each other.

Digital Repository

A system for storing, managing, and providing access to digital content.

DOI (Digital Object Identifier)

A persistent identifier used to permanently link to digital content, commonly used for journal articles.

DRM (Digital Rights Management)

Technology used to control access to and use of digital content.

E-book

An electronic version of a printed book that can be read on computers, tablets, or dedicated e-readers.

Institutional Repository

A digital archive of an institution’s intellectual output, including research papers, theses, and datasets.

OA (Open Access)

Free, unrestricted online access to research articles and other scholarly content.

OPAC (Online Public Access Catalog)

The library’s online catalog that patrons use to search for and locate materials.

Proxy Server

A server that allows off-campus users to access licensed electronic resources as if they were on campus.

SIP2 (Standard Interchange Protocol)

A protocol that allows self-checkout machines and other devices to communicate with the library system.

Z39.50

A protocol for searching and retrieving bibliographic data from remote databases.

Reference & Research

Bibliography

A list of sources used in research or writing, or a comprehensive list of works on a particular subject.

A search technique using operators (AND, OR, NOT) to combine or exclude keywords.

Citation

A reference to a published or unpublished source that identifies the work.

Database

An organized collection of structured information, typically searchable electronically.

Full Text

Complete content of an article or document, as opposed to just an abstract or citation.

Impact Factor

A measure of how frequently articles in a journal are cited, used to assess journal prestige.

Index

A systematic guide to the contents of publications, listing subjects, names, or topics with references to where they appear.

Peer Review

The evaluation of scholarly work by experts in the field before publication.

Primary Source

Original materials created at the time being studied (letters, photographs, speeches, etc.).

Reference Collection

Materials designated for in-library use only, typically including encyclopedias, dictionaries, and handbooks.

Referral

Directing a patron to another library or information source better suited to answer their question.

Secondary Source

Materials that analyze, interpret, or discuss primary sources.

Subject Guide (LibGuide)

A curated collection of resources on a specific topic or for a particular course.

Library Systems & Automation

Batch Processing

Performing the same operation on multiple records or items simultaneously.

Bibliographic Utility

A shared cataloging database used by multiple libraries, such as OCLC WorldCat.

Cron Job

A scheduled automated task that runs at specific times or intervals.

Data Migration

The process of transferring data from one system to another, such as when changing library systems.

ILS (Integrated Library System)

Software that manages all library operations including cataloging, circulation, acquisitions, and patron management.

LSP (Library Services Platform)

Next-generation library systems designed for managing both print and electronic resources.

OCLC (Online Computer Library Center)

The world’s largest bibliographic database and library cooperative.

Patron Record

Database entry containing a library user’s personal information, borrowing history, and account status.

REST API

A modern interface allowing external systems to interact with library software.

Self-Checkout

Automated station allowing patrons to check out materials themselves without staff assistance.

SIS (Student Information System)

Administrative software managing student enrollment data, often integrated with library systems for patron management.

SQL (Structured Query Language)

The programming language used to query and manipulate library databases.

Common Acronyms

Acronym Full Term
ALA American Library Association
API Application Programming Interface
BISAC Book Industry Standards and Communications
DDC Dewey Decimal Classification
DOI Digital Object Identifier
DRM Digital Rights Management
EDI Electronic Data Interchange
FRBR Functional Requirements for Bibliographic Records
ILL Interlibrary Loan
ILS Integrated Library System
ISBN International Standard Book Number
ISSN International Standard Serial Number
LCSH Library of Congress Subject Headings
LMS Library Management System (or Learning Management System in education)
LSP Library Services Platform
MARC Machine-Readable Cataloging
OA Open Access
OCLC Online Computer Library Center
OPAC Online Public Access Catalog
RDA Resource Description and Access
RFID Radio Frequency Identification
SIP2 Standard Interchange Protocol
SSO Single Sign-On

Usage in Context

Understanding these terms allows librarians to:

  • Communicate effectively with colleagues and vendors
  • Navigate professional literature and conferences
  • Train new staff and volunteers
  • Explain library services to patrons
  • Implement new systems and technologies
  • Participate in professional development

Resources for Further Learning

Need help implementing these concepts in Koha? Explore our Koha Knowledge Base for practical guides and tutorials.

Next Steps

After Deployment
Post-Installation Setup
Recommended
Security Best Practices
Keep It Running
Monitoring & Maintenance

More in Resources & Guides

Was this article helpful?

Thanks for your feedback!