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Independent College Dublin: The Dewey Decimal System

The Dewey System Explained

It is a library system of classification for books and materials using ten subject areas. The ten main classes or subject areas are:

000 Computer science, information & general works

100 Philosophy & psychology

200 Religion

300 Social sciences

400 Language

500 Science

600 Technology

700 Arts & recreation

800 Literature

900 History & geography

Items are classified according to these subject areas and thus numbers (and may also include some letters to denote authors). Each library item receives a call number to classify it and assist library users in finding it. For example, at Independent College library much of the collection belongs to the subject area of Law which is classified as a Social Science. This means that items in the Law collection will have a base call number of 300.

How to read a Dewwy Call Number

341. 48 REH

300 Social Sciences

340 Law, and 341 International Law

48 further subject classification  and REH for the author surname (REHman)  

Books are arranged sequentially. The first number of a Dewey Decimal call number indicates the general class the call number falls within. It is rad as a whole number. In this example, the book is located under the 300s, which is where books on social sciences are classed. If there is a second or third selection of numbers, these indicate more specific divisions and subject areas, and in this case, it is LAW and INTERNATIONAL LAW.

Numbers following the first 3 numbers are read as decimals. The numbers further define the subject of the book often with letters identify the author.

The title is International Human Rights: A Practical Approach by Javaid Rehman with a call number 341. 48 REH

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