Information Sources – Nature, Characteristics, Types, and Formats

Information Sources – Nature, Characteristics, Types, and Formats

Introduction

In the contemporary landscape of the global knowledge society, information has emerged as a critical asset and the primary driving force behind human progress, socio-economic development, and scholarly research. The generation of information is a continuous and dynamic phenomenon, originating from human cognitive activities such as empirical observation, scientific experimentation, speculative imagination, logical reasoning, and everyday experiences. As these raw intellectual outputs are recorded and packaged, they are transformed into information sources that libraries and documentation centres systematically acquire, organise, and disseminate to satisfy the diverse needs of their users. For any candidate preparing for advanced competitive examinations in Library and Information Science (such as UGC NET, SET, or State PSC), a comprehensive, analytical understanding of the nature, characteristics, structural classifications, and evolving formats of information sources is absolutely indispensable.

Key Definitions

• Data: Raw, unorganised, and uninterpreted facts, numbers, or symbols that exist without context, representing an objective statement of reality or a direct observation of physical and social phenomena.

• Information: Data that has been systematically processed, structured, interpreted, and contextualised in a manner that renders it meaningful, relevant, and useful to a recipient for a specific decision-making purpose.

• Knowledge: The cognitive internalisation, comprehension, and practical application of information within the human mind, enriched by experience, context, critical reflection, and integration into the individual's existing intellectual framework.

• Information Source: Any physical, digital, human, or institutional entity that produces, contains, or transmits recorded or unrecorded knowledge to satisfy an informational requirement.

• Information Resource: An overarching organizational concept that encompasses the collective information assets of an institution, including raw data, technology systems, hardware, personnel, and information management infrastructure.

• Document: A distinct piece of written, printed, or electronic matter that provides authentic evidence, serves as an official record of human thought, or contains structured information for communication.

Detailed Theory

1. Nature and Characteristics of Information Sources

The qualitative utility of any information source depends on its fundamental characteristics, which dictate how effectively it can satisfy the needs of researchers, students, and professionals. High-quality information must possess attributes of high accuracy, currency, completeness, reliability, and precision, and it must be targeted appropriately to the user.

From an analytical standpoint, information can be classified as factual or analytical. Factual information consists of indisputable, objective statements that remain constant regardless of the retrieval context, such as data found in dictionaries, almanacs, or atlases. Conversely, analytical information represents an expert's interpretation, evaluation, or analysis of factual data, which is typically found in scholarly books, research articles, and subject treatises.

Furthermore, information may be objective or subjective. Objective information presents a balanced, non-judgmental, and comprehensive reporting of all sides of an issue, whereas subjective information reflects a particular perspective, personal opinion, or biased argument. The physical medium and overall structural format of these sources also dictate their accessibility; for instance, digital and electronic media have fundamentally transformed retrieval speeds through keyword indexing, Boolean operators, and remote multi-user access.

2. The Great Categorisation Models of Library Science

The vast and rapid expansion of literature—often referred to as the "information explosion"—has made the systematic categorisation of information sources a primary necessity for retrieval. To impose intellectual order on this chaotic universe of knowledge, several eminent library and information science scholars have proposed structural models based on varying criteria such as content, format, and physical media.

                             INFORMATION SOURCES

                                      │

         ┌────────────────────────────┴────────────────────────────┐

    DOCUMENTARY                                             NON-DOCUMENTARY

         │                                                         │

   ┌─────┼─────────────┐                             ┌─────────────┴─────────────┐

PRIMARY SECONDARY TERTIARY                       FORMAL                      INFORMAL

   │     │             │                             │                           │

   │     │             └─ Directories                ├─ R&D Institutions         ├─ Conversation with peers

   │     │                Guides to Lit.             ├─ Universities             ├─ Invisible Colleges

   │     │                Bibliography of            ├─ Gov. Departments         └─ Technological Gatekeepers

   │     │                Bibliographies             └─ Learned Societies

   │     │

   │     └─ Textbooks, Reference Books, Indexing/Abstracting Journals

   │

   └─ Research Journals, Patents, Standards, Theses, Dissertations

A. S. R. Ranganathan’s Classification

Dr. S. R. Ranganathan, the father of library science in India, developed a dual classification system. He categorised documents firstly by the volume of their intellectual thought content, and secondly by their physical recording media.

• Macro vs. Micro Documents: Documents that embody a broad, complete, and self-contained subject are termed macro documents (such as an entire textbook). In contrast, those that embody a highly focused, specialized, and narrow topic of research are designated as micro documents (such as a specific journal article).

• The Media of Recording: Dr. Ranganathan classified documents into four distinct evolutionary stages based on their physical formats:

  1. Conventional Documents: Traditional materials recorded on paper, utilizing phonetic symbols or scripts, such as books, journals, maps, and atlases.

  2. Neo-Conventional Documents: Highly specialized records presenting data in non-traditional formats, such as standards, specifications, patents, and data sheets.

  3. Non-Conventional Documents: Materials recorded on non-paper media or highly reduced in size, requiring auxiliary reading devices, including microforms, audios, visuals, and audio-visual resources.

  4. Meta Documents: Direct instrument records of natural or social phenomena produced automatically without any human cognitive intervention, such as satellite telemetry, radar outputs, and automated meteorological charts.

B. C. W. Hanson’s Binary Classification (1971)

Writing in his seminal work, Introduction to Science Information Work, published by ASLIB in 1971, C. W. Hanson proposed a simplified, highly functional division of documentary sources into two core categories. Hanson argued that there is no need for a tertiary category in practical information work.

• Primary Sources: These are original documents that exist in their own right, containing first-hand observations, experiments, and the original formulation of new theories. Hanson included books, periodicals, dissertations, reports, and patents here. Interestingly, he argued that articles in encyclopaedias and textbooks could be considered primary sources if they presented a topic in a completely new, specially-written format for the first time.

• Secondary Sources: These consist of publications that present the contents of primary documents in a condensed form or list them in a helpful, systematic arrangement to facilitate retrieval, such as catalogues, bibliographies, and indexing services.

• Primary/Secondary Hybrid: Hanson acknowledged that certain publications, like theses or conference proceedings, often exhibit a mix of both primary research and secondary literature reviews, though he maintained that a binary division was most practical.

C. Denis Grogan’s Three-Tiered Classification

Denis Grogan, the renowned British information scientist, formulated the most widely accepted and universally applied model in Library and Information Science. Grogan's classification is strictly based on the level of intellectual reorganisation that the information undergoes as it moves away from its original state.

• Primary Sources: These represent the very first formal appearance of newly generated knowledge in print or electronic format. They contain raw data, new interpretations of known facts, and original research that has not passed through any external filtering, condensation, or evaluation mechanism. Examples include peer-reviewed journal articles, patents, standards, theses, technical reports, and laboratory notebooks.

• Secondary Sources: These are derivative works built entirely upon primary sources. They collect, digest, analyse, translate, and systematically arrange primary information into a highly organized and digestible format. They act as a bibliographical key to primary literature, helping users navigate the scattered mass of original papers. Examples include indexing and abstracting periodicals, textbooks, bibliographies, and reference books like dictionaries and encyclopaedias.

• Tertiary Sources: These are the last to appear in the publishing cycle. They do not carry actual subject knowledge or original analyses; instead, they serve as "information about information," acts as an instructional guide to locate primary and secondary sources. Examples include directories, yearbooks, guides to literature, bibliography of bibliographies, and guides to reference sources.

D. George S. Bonn and Linda C. Smith’s Classification

Bonn and Smith focused their classification on scientific and technical literature, categorizing sources into three distinct tiers with some notable variations.

• Primary Sources: Their list includes periodicals, festschriften, conference proceedings, research reports, research monographs, preprints, patents, standards, dissertations, and trade literature (manufacturers' literature).

• Secondary Sources: Uniquely, Bonn and Smith included translations, Critical Tables, machine-readable bibliographic databases, and databanks within secondary sources, recognizing the role of electronic media in reorganizing original records.

• Tertiary Sources: They placed textbooks under the tertiary category, along with directories and guides to the literature, arguing that textbooks merely repackage established, compiled facts for instructional purposes.

E. R. S. Giljarevskij’s Binary Model

The Russian information scientist R. S. Giljarevskij proposed a strict, comprehensive binary classification that covers all subject areas, not just science and technology. Giljarevskij rejected the concept of a tertiary category, dividing all information records into either primary or secondary sources.

• Primary Sources: His primary category is remarkably broad, including monographs, collected papers (festschriften), conference proceedings, textbooks, manuals, official publications, patents, technical catalogues, scientific reports, theses, standards, preprints, manuscripts, and computerized data files.

• Secondary Sources: Giljarevskij placed reference literature, reviews, abstracting journals, express bulletins, standards indexes, and library catalogues into the secondary group.

F. K. Subramanyam’s Exhaustive Model

K. Subramanyam provided an incredibly detailed and exhaustive classification system that was designed specifically for scientific and technical literature. Unlike other theorists who focused primarily on macro-documents, Subramanyam made sure to include micro-documents and unpublished records.

• Primary Sources: His list encompasses laboratory notebooks, diaries, medical records, personal correspondence, videotapes of experiments, machine-generated graphs/tables, preprints, reprints, short communications in primary journals, conference papers, technical reports, and computer programs.

• Secondary Sources: Subramanyam's secondary category includes bibliographies, indexes, abstracts, current awareness services, handbooks, directories, yearbooks, almanacs, reviews, monographs, textbooks, and encyclopaedias.

3. The Academic Debate: Lack of Unanimity in Categorisation

One of the most frequent areas tested in competitive examinations is the structural overlap and lack of unanimity among information theorists regarding certain documents. Because "context is everything," a single document can be classified differently depending on how and why it is being used.

• The Textbook Controversy: A classic textbook is placed under the primary category by Giljarevskij (arguing it is a first-time unique presentation of a subject), under the secondary category by Grogan and Subramanyam (since it digests and summarizes primary research), and under the tertiary category by Bonn and Smith (as it merely repackages consolidated ideas for students). In LIS, the consensus is to treat textbooks as secondary sources, as they contain very little original research.

• The Monograph Debate: Bonn and Smith consider research monographs to be primary sources, whereas Grogan and Subramanyam classify them as secondary. The distinction lies in the content: a research monograph reporting the original results of a specific experiment or survey is a primary source, while a monograph culling and compiling data from various existing primary works (such as Rice in India) is a secondary source.

• Directories and Lists of Research in Progress: Directories are typically classified as tertiary sources by Grogan and Bonn but as secondary sources by Subramanyam. However, because the compiler of a directory or a list of ongoing research collects raw, first-hand data directly from scientists via questionnaires, these can also be argued to be primary sources.

4. Primary Sources (Print and Electronic Formats)

Primary sources are the ultimate foundation stones of any subject discipline, providing the raw evidence upon which all subsequent analyses are built.

• Research Periodicals (Journals): These are the most vital channels for scholarly communication. They publish original, peer-reviewed research papers, letters, and short communications, representing the first formal announcement of an invention or discovery.

• Technical Reports: These are detailed documents issued by research organizations or government departments, describing the progress, methodology, and results of a technical or scientific investigation. They are categorized into technical, administrative, and trip reports.

• Patents: A patent is a legal contract granted by a government to an inventor, giving them exclusive rights to exploit their invention for a limited period (typically 20 years). Patent specifications are extremely rich sources of primary technical information, often describing inventions that are never published anywhere else.

• Standards and Specifications: Standards are documents established by consensus and approved by a recognized body (e.g., ISO, BIS) that provide rules, guidelines, or characteristics for activities or their results. They are highly precise, authoritative primary sources.

• Theses and Dissertations: These are detailed research documents submitted by candidates for academic degrees (such as a PhD). They present original investigations, detailed bibliographies, and new methodologies, serving as primary sources of the highest academic rigor.

• Grey Literature: This refers to written materials that are produced on all levels of government, academics, business, and industry in electronic and print formats, but which are not controlled by commercial publishers. Examples include working papers, preprints, committee reports, and government notifications.

5. Secondary Sources (Print and Electronic Formats)

Secondary sources are created to overcome the problems associated with primary literature, which is highly scattered, unorganized, and difficult to locate.

• Indexing and Abstracting Periodicals: These are systematic compilations that list citations and metadata of primary articles. Indexing periodicals provide bibliographical details, while abstracting periodicals (such as Chemical Abstracts or Indian Science Abstracts) provide a concise, structured summary (abstract) of the original research article.

• Reference Books: These include dictionaries (which define language, terminology, and etymology), encyclopaedias (which provide detailed background summaries written by experts), and handbooks and manuals (which offer compilations of raw data, tables, and instructions).

• Bibliographies: A systematic, compiled list of published documents on a specific subject, by a particular author, or published in a specific nation (National Bibliography). Bibliographies do not supply original documents; they act as a bridge between the user and the primary literature.

6. Tertiary Sources (Print and Electronic Formats)

Tertiary sources acts as guides, helping the user search through the vast arrays of primary and secondary materials.

• Bibliography of Bibliographies: A compilation that lists bibliographies on various subjects, helping researchers locate the specific bibliographical keys they need for their literature search.

• Directories: These are systematic listings of persons, organizations, or products, providing addresses, contact information, and institutional details.

• Guides to Literature: These are publications that introduce a researcher to the key journals, databases, reference works, and institutions within a specific subject field, helping them chart a search strategy.

• Almanacs and Yearbooks: An almanac is an annual publication containing statistical, descriptive, and astronomical data. A yearbook focuses on recording the events, statistics, and developments of the preceding year. Both are crucial ready-reference tertiary tools.

7. Non-Documentary Sources of Information

Non-documentary sources represent information that is not recorded in conventional document formats. They provide instant communication, bypass the delays of formal publishing, and are easy to use.

• Human Sources: Individual experts, consultants, colleagues, and common people.

  • Invisible Colleges: Informal social networks of scientists and subject experts who communicate and exchange ideas, papers, and preprints directly, bypassing formal library and publishing channels.

  • Technological Gatekeepers: Experts within an organization who read extensively, maintain high external contacts, and informally pass on the latest relevant information to their colleagues.

• Institutional/Organisational Sources: Universities, research and development laboratories, learned societies, government ministries, database vendors, and referral centres. A Referral Centre does not supply documents or actual answers; it directs the user to the precise expert or institution that can provide the information.

• The Internet and World Wide Web: The ultimate non-documentary network that hosts database systems, search engines, subject directories, and institutional repositories.

Tables and Comparisons

Table 1: Comprehensive Comparison of Documentary Classifications

Scholar	Year/Context	Primary Category	Secondary Category	Tertiary Category	Special Highlights
S. R. Ranganathan	Classified Catalogue Code	Conventional & Neo-Conventional	Not used in this media model	Non-Conventional & Meta-documents	Focuses on volume of thought and recording media.
C. W. Hanson	1971 ASLIB Publication	Original publications, journals, patents, books	Catalogues, bibliographies, abstracts, indexes	Explicitly rejected	Proposed a hybrid "Primary/Secondary" group.
Denis Grogan	Standard LIS Model	Journals, patents, standards, reports, theses	Textbooks, indexes, abstracts, monographs	Directories, yearbooks, guides to literature	Universally accepted; based on level of reorganisation.
Bonn & Smith	Sci-Tech Literature	Journals, conference papers, patents, preprints	Handbooks, databases, databanks, translations	Textbooks, directories, guides to literature	Uniquely places textbooks under the tertiary category.
R. S. Giljarevskij	Russian School	Monographs, textbooks, patents, standards, reports	Reference literature, reviews, library catalogues	Explicitly rejected	Covers all literature disciplines, not just science.
K. Subramanyam	Exhaustive Sci-Tech	Laboratory notebooks, journals, letters, patents	Bibliographies, directories, handbooks, textbooks	Not treated as separate	Heavily focuses on unpublished and micro documents.

Table 2: Structural Characteristics of Primary, Secondary, and Tertiary Sources

Diagnostic Feature	Primary Sources	Secondary Sources	Tertiary Sources
Intellectual Status	Original, uninterpreted, raw, and unassimilated.	Interpreted, analysed, digested, and evaluated.	Compiled, distilled, and factual representations.
Timing in Pub. Cycle	First in the cycle; published immediately.	Second in the cycle; requires primary works to exist.	Last in the cycle; digests primary and secondary works.
Primary Utility	Communicates new discoveries and raw data.	Helps identify, locate, and digest primary sources.	Introduces a subject and guides users to resources.
Structural Level	Disorganised, scattered, and unassimilated.	Organized and arranged systematically.	Synthesized into highly structured reference tools.
Key Examples	Patents, standards, theses, research journals.	Textbooks, dictionaries, indexes, abstracts.	Directories, guides, yearbooks, almanacs.

Chronological Timeline of Information Format Developments

[Ancient Era] ──► Oral communication, clay tablets, papyrus sheets, and vellum manuscripts.

       │

[1450s]       ──► Johannes Gutenberg invents movable type printing, sparking mass book production.

       │

        ──► Birth of the scholarly journal (e.g., Journal des Sçavans; Philosophical Transactions).

       │

[Late 1800s]  ──► Mass explosion of print literature; rise of formal indexing and abstracting tools.

       │

[1970s]       ──► Launch of computerized database networks (e.g., Lockheed DIALOG, MEDLINE).

       │

[1980s]       ──► Rise of physical CD-ROM databases as offline electronic reference libraries.

       │

[1990s]       ──► Tim Berners-Lee invents the World Wide Web; hypermedia and HTML documents emerge.

       │

[2000s-Pres.] ──► Open Access, institutional repositories, semantic web searching, and real-time data.

 Remember for Exams! (Memory Tricks & Exam Tips)

• Mnemonic for Grogan's Categories: Primary, Secondary, Tertiary \(\rightarrow\) PST (think Post Service Tax to remember the exact order of appearance).

• Mnemonic for Ranganathan's Media: Conventional, Neo-conventional, Non-conventional, Meta document \(\rightarrow\) CNNM (think of CNN News Mobile).

• EXAM TRICK: In UGC NET, if you see the term "Bibliography of Bibliographies" or "Guides to Literature", mark them as Tertiary Sources immediately.

• EXAM TRICK: While many think of them as guides, "Textbooks" are classified as Secondary Sources under Denis Grogan's standard system.

• EXAM TRICK: A "Patents Specification" is ALWAYS a Primary Source because it represents the first official disclosure of a new invention.

• HIGHLY TESTED FACT: The term "Invisible College" represents informal communication among scientists. It was historically coined by Derek de Solla Price and studied heavily in LIS.

• HIGHLY TESTED FACT: The term "Technological Gatekeeper" was introduced by Thomas J. Allen in 1968 to describe internal organization information guides.

Previous-Year Examination-Oriented Facts (Frequently Asked Areas)

1. Denis Grogan is famous in LIS for classifying scientific literature into Primary, Secondary, and Tertiary sources on the basis of its reorganisation level.

2. C. W. Hanson did not use a tertiary category in his classification, preferring a strict binary division.

3. S. R. Ranganathan created the concept of "Meta-documents", which refer to records produced directly by mechanical instruments without any human cognitive intervention.

4. Patents, Standards, and Theses are categorized as Primary sources by almost all LIS experts.

5. Indexing and Abstracting services (like LISA or CAS) serve as keys to primary literature and are classified as Secondary sources.

6. A Referral Centre is a vital non-documentary organization that acts as a clearinghouse, directing users to appropriate experts or databases rather than supplying materials itself.

7. Translations represent a change in language while retaining the original thought, making them Secondary sources.

Glossary of Important Terms

• Abstracting Journal: A secondary periodical that provides concise, objective summaries of original primary articles, together with full bibliographical citations.

• Documentary Source: Any source of information that is recorded on a physical, optical, or digital medium.

• Invisible College: An informal, unrecorded network of researchers and experts who communicate, share preprints, and collaborate directly, bypassing libraries.

• Meta Document: A document produced directly by a recording instrument without human mediation, such as satellite photographs or seismograph charts.

• Preprint: A manuscript of a research paper that is shared informally before it undergoes formal peer review and publication.

• Technological Gatekeeper: A highly active professional within an organization who tracks external literature, communicates with outside experts, and shares that information with colleagues.

• Tertiary Source: A guide or reference tool that helps researchers locate and navigate primary and secondary sources.

Quick Revision Notes

• Data, Information, and Knowledge: Data consists of raw facts; Information is processed data with meaning; Knowledge is internalized information applied in context.

• Information Sources: Broadly split into Documentary (recorded) and Non-Documentary (unrecorded, human, or institutional).

• Primary Documentary: Journals, research reports, patents, standards, theses, dissertations, and laboratory notebooks.

• Secondary Documentary: Reference books, textbooks, bibliographies, translations, indexing, and abstracting services.

• Tertiary Documentary: Directories, yearbooks, almanacs, guides to literature, and bibliography of bibliographies.

• Ranganathan’s Model: Broadly classified by thought volume (macro vs. micro) and physical medium (conventional, neo-conventional, non-conventional, and meta-documents).

• Hanson’s Model: A highly functional binary model (Primary and Secondary).

• Grogan’s Model: The universal standard, using a three-tier system based on the level of information reorganisation.

• Non-Documentary Channels: Human experts, technological gatekeepers, invisible colleges, organizations (referral centres), and the World Wide Web.

One-Page Quick Revision Summary

                      [THE NATURE OF INFORMATION]

                   Raw Facts (Data) ────► Processed & Contextualised (Information) ────► Applied (Knowledge)

                                                 │

                                 ┌───────────────┴───────────────┐

                          DOCUMENTARY                     NON-DOCUMENTARY

                                 │                               │

             ┌───────────────────┼───────────────────┐           ├─ Humans

          PRIMARY            SECONDARY            TERTIARY       │   ├─ Invisible Colleges

             │                   │                   │           │   └─ Tech Gatekeepers

      Original, raw,       Digested, compiled,   Guides & keys   │

       unfiltered.          systematic key to    to literature.  ├─ Institutions

       First appearance.    primary works.       Last to appear. │   ├─ R&D Organizations

             │                   │                   │           │   └─ Referral Centres

      ├─ Journals   ├─ Textbooks   ├─ Directories    │

      ├─ Patents    ├─ Dictionaries ├─ Yearbooks└─ Internet & WWW

      ├─ Theses     ├─ Indexes     ├─ Almanacs

      └─ Standards  └─ Abstracts   └─ Guides

Essential Exam Match-ups!

• Ranganathan: Conventional, Neo-Conventional, Non-Conventional, Meta-Documents.

• C. W. Hanson: Strict Binary Division (Primary and Secondary only).

• Denis Grogan: Three-tiered structural division (Primary, Secondary, and Tertiary).

• T. J. Allen: Technological Gatekeepers.

• Derek de Solla Price: Invisible Colleges.

• Referral Centre: Directly routes users to specific experts or organizations.

• Translation: Language shift of original documents \(\rightarrow\) Secondary source.