Preparing for Academic Writing & Speaking
Doing the research
The Dewey Decimal System
Every book in the library has a call number (or class number) which helps you to find it. The call number identifies each individual book and will be found on the spine of the book. It also indicates the position of a book on a shelf. The most common system of numbering the books in the UK is the Dewey Decimal system.
In this system, books in the same subject area will be shelved together. Call numbers usually consist of numbers and letters. The number represents the subject of the book and the letters usually represent the author.
For example, in the University of Hertfordshire library:
Academic writing course by R. R. Jordan is 428.24 JOR
Study listening by Tony Lynch is 428.4207 LYN
The Dewey Decimal system classifies books as follows:
000-099 General works (including libraries, journalism, general encyclopedias, etc.)
100-199 Philosophy and Related Disciplines
200-299 Religion
300-399 Social Sciences
400-499 Language
500-599 Natural Science and Mathematics
600-699 Technology (Applied Science)
700-799 Arts
800-899 Literature
900-999 General Geography and History
Each of these classes can be divided into ten smaller classes. For example:
500 Natural Science
510 Mathematics
520 Astronomy & allied sciences
530 Physics
540 Chemistry & allied sciences
550 Science of Earth and other worlds; Geology
560 Palaeontology; Fossils
570 Life sciences; Biology
580 Botany
590 Zoology
Each of these classes may be divided further, for example:
500 Science
590 Zoology
591 Animals – habits and behaviour
592 Invertebrates – animals without backbones
593 Sponges, corals, jellyfish etc.
594 Molluscs – snails, shell-fish, sea-shells
595 Other invertebrates – worms, crabs, spiders
596 Vertebrates – sea squirts and sea grapes
597 Fishes
598 Reptiles and birds
599 Mammals
Even more subdivisions can follow, represented by decimal points. The number of digits will depend on how specific the topic of the book is. For example:
500 Natural Science
590 Zoological Sciences
595 Other invertebrates
595.7 Insects
595.78 Lepidoptera
595.789 Butterflies
So we see that Butterflies (595.789) is a subdivision of Lepidoptera (595.78) which is a subdivision of Insects (595.7). This in turn is a subdivision of Other Invertebrates (595) which is a subdivision of Zoological Sciences (590-599).
The second part of the call number may consist of the initial letters of the author’s surname. For example:
595.789 BRU is Butterflies by Beth Wagner Brust
595.789 EHL is Waiting for wings by Lois Ehlert
595.789 FIS is Life of the Butterfly by Heiderose & Andreas Fischer-Nagel
595.789 GIB is Monarch Butterfly by Gail Gibbons