Information Sources by Content: An Overview

Edited by Asheesh Kamal

LIS Cafe Website, 2022

 

Information sources are categorised as:

(1) Primary,

(2) Secondary

(3) Tertiary.

 

By content, information sources are categorised as primary, secondary and tertiary. This categorisation is mainly valid for scientific literature. We shall deal with them here in the same order.

 

a) Primary Sources

Primary sources usually contain original scientific contributions that have not appeared anywhere earlier. They are the first account of original research presented before the world audience. The account may be of a completely new discovery or invention; new interpretations of previously known facts; new application of a substance, devise, etc.; new process to manufacture a product; new method of chemical analysis; and so on.

The types of documents that are considered as primary sources are

• Research periodicals.
• Technical reports.
• Conference documents.
• Theses/dissertations.
• Patents;
• Standards;
• Trade catalogues;
• Laboratory notebooks;
• Diaries of scientists;
• Correspondence; and so on.

 

b) Secondary Sources

These sources contain material derived from primary sources and organised or arranged following some systematic order. For example, an indexing periodical is a secondary source in as much as information recorded here are all derived from primary sources like primary periodicals, conference documents, and so on. These sources bring together in one place the information on literature scattered in various primary sources. The information may be in the form of just citations, abstracts, reviews, or popular articles. Secondary sources are in fact keys to the primary literature.

The types of documents that are included in secondary sources are

• Bibliographies;
• Indexing periodicals;
• Abstracting periodicals;
• Reviewing periodicals;
• Textbooks;
• Monographs;
•  Treatises;
• And reference books like dictionaries,
• Encyclopaedias,
•  Handbooks,
• Manuals,
• Data books,
• Catalogues,
• Biographical dictionaries,
• Gazetteers,
• Guide books,
• Maps,
• Atlases,
• Globes, and so on.

 

c) Tertiary Sources

Tertiary sources are of three types:

(1) sources that are purely based on secondary sources e.e.g.

bibliography of bibliographies.

(2) sources that are key to primary and secondary sources, e.g.

guides to reference sources; and

(3) sources like research in progress.

 

 

Reference:

1. Wikipedia

2. IGNOU Study Materials