Nature, Characteristics and Classification of Information Sources
Information sources are conventionally classified in two overlapping ways: by generation stage (primary, secondary, tertiary) and by form (documentary — recorded in a physical/digital document — versus non-documentary, such as an expert's oral testimony).
Primary Information Sources
Original, first-hand accounts of research or events, in print and electronic form:
- Journals — periodicals reporting new research findings.
- Conference Proceedings — papers presented at conferences/seminars.
- Patents — legal documents describing new inventions.
- Standards — documented specifications (e.g., ISO, BIS standards).
- Theses & Dissertations — original research submitted for a degree.
- Trade Literature — catalogues, product manuals, and technical bulletins from manufacturers.
Secondary Information Sources
Sources that organise, digest, or repackage primary information for easier access:
- Dictionaries and Encyclopedias — definitional and topical background information.
- Bibliographies — systematic lists of documents on a subject or by an author.
- Indexing and Abstracting Services — point to and summarise primary literature (e.g., LISA, Scopus).
- Statistical Sources — compiled numerical data (e.g., census reports).
- Handbooks and Manuals — condensed, practical reference information for a field.
Tertiary Information Sources
Sources that guide the user to primary and secondary sources rather than containing subject content themselves — Directories (lists of organisations/individuals with contact details), Year Books (annual compilations of facts/statistics/events), and Almanacs (annual publications with calendars, statistics, and miscellaneous facts).
Reference Sources by Type
| Type | Example use |
|---|---|
| Bibliographical | Identifying what has been published on a subject/by an author |
| Biographical | Facts about a person's life (Who's Who directories) |
| Educational | Information on courses, institutions, and qualifications |
| Language | Dictionaries, thesauri, translation aids |
| Geographical | Atlases, gazetteers, maps |
Electronic Information Resources
- Subject Gateways — curated portals linking to quality-vetted resources in a subject area.
- Web Portals — single-entry-point websites aggregating multiple services/resources.
- Bulletin Boards and Discussion Forums/Groups — platforms for asynchronous community discussion and information exchange.
Databases
| Type | Description |
|---|---|
| Bibliographic | Records citation details of documents (e.g., Scopus, Web of Science) |
| Numeric | Stores statistical/numerical data |
| Full text | Provides complete text of documents (e.g., JSTOR) |
| Multimedia | Combines text, image, audio, and video content |
| Open Access | Freely accessible without subscription barriers (e.g., DOAJ) |
Institutional and Human Resources; Evaluation of Sources
Beyond documents, institutional resources (libraries, archives, data centres) and human resources (subject experts, consultants) also serve as valuable information sources. When evaluating any reference source or web resource, key criteria include:
- Authority — credentials of the author/publisher.
- Accuracy — verifiability and freedom from error.
- Currency — how up to date the information is.
- Objectivity — presence of bias or vested interest.
- Coverage/Scope — comprehensiveness relative to the need.