Most Important Information Sources

Previous Year-based most important types of information sources are explained here. It is also known as a documentary source.

In 1971, C. W. Henson classified the sources into two types published in C. W. Henson Classification.

1. Primary Sources

2. Secondary Sources

In 1982, Denis Grogan classified the documentary source into three types:

1. Primary Sources

2. Secondary Sources

3. Tertiary Sources

Some examples of Sources

1. Primary Sources (Original and Nascent Information)

1. Patents
2. Primary Periodicals
3. Conference Documents
4. Reports
5. Monographs
6. Official Publications
7. Standards
8. Trade Literature
9. Thesis and Dissertations
10. Project Reports
11. Interviews
12. Proceeding of meetings
13. Laboratory Notebook
14. Reprints
15. Letters, Pamphlets
16. Diaries
17. Memoranda
18. Medical Records
19. Artifacts(Coins, Fossils, Furniture etc.)
20. Audio Recordings
21. Internet communication on email (listserver)
22. Photographs
23. Video Recordings
24. Speeches
25. Original Documents (Birth Certificates, Marriage Certificates etc.)
26. Records of Govt. Organisations
27. Auto Biography
28. Anthologies of papers
29. Manuscripts 

2. Secondary Sources (Information collected from primary sources)

1. Indexes
2. Reviews
3. Translations
4. Bibliographies
5. Bibliographical Work
6. List of research in progress
7. Textbooks
8. Bibliographic Database
9. Indexing and Abstracting Periodicals
10. State-of-the-art report
11. Trend Report
12. Technical Digest
13. Biography

14. Reference Sources

- Encyclopedia (General and Subject Encyclopedia)

- Dictionaries (General, Subject, Monolingual, Bilingual and Multilingual Dictionaries)

- Handbooks [deals with established knowledge]

- Manuals

- Databooks and Tables

- Directories

- Almanac [covers current and retrospective information]

- Map

- Atlases

- Globes

- Gazetteers

- Guide Books

- Yearbooks (General, Subject, Regional and National Yearbooks) 

[covers current information]

3. Tertiary Sources (Information compiled and collected from primary and secondary sources)

1. Union Catalogues
2. Bibliography of Bibliographies
3. Guides to Literature
4. Directory of Directories
5. Guide to reference sources
6. Directories (Sometimes)
7. Yearbooks (Sometimes)

Most Important confusing Questions:

1. Documents का सूचना विशेषताओं के आधार पर विभाजन - based on Hanson & Grogan Principle

2. Documents का भौतिक विशेषताओं के आधार पर विभाजन - based on S R Ranganathan Principle