What is the Dewey Decimal Classification System?
A man named Melvil Dewey developed the Dewey Decimal Classification System in 1876. He thought that it would help libraries organize their books better if each book was given a number according to what it was about. That way, all books with the same subject would be close to each other on the shelf. That's what "classification" means.
How is it organized?
The word "decimal" refers to numbers that are based on 10 (ten). You will see that there are 10 basic categories in the Dewey Decimal system, and each of those categories is further split into 10 categories, and so on. The number 10 has always been a good number for people to use in counting things because we have 10 fingers!
How can I find things?
Each one of the 10 major categories in the Dewey Decimal system covers a different subject. For example, the 300 category includes everything about the Social Sciences, like Government or Law. The 800 category includes everything about Literature. Once you get used to how things are organized, you'll find it very easy to locate the information you're looking for.
Why is the Dewey system still used?
Melvil Dewey thought up this system just for organizing books, because there wasn't much else in libraries back in 1876. However, the Dewey Decimal system is also very good for organizing other kinds of information, like websites. Today, many libraries still use the Dewey Decimal system, even though they might have things like videotapes, compact discs (CDs), and computer files as well as books in their collections.
Should the Dewey system be reorganized?
You may notice that the Dewey Decimal system pays more attention to American and European subjects than to those of other cultures. Back in 1876, many people didn't understand the importance of a global perspective and learning about other cultures. The Dewey system still reflects that old outlook because it would be very hard for libraries to completely change how they are organized. Someday, though, we hope that the Dewey Decimal system will more fairly represent the diversity of our world.
Here are the ten main classes in the Dewey Decimal System:
000 Generalities
100 Philosophy
200 Religion
300 Social Sciences
400 Languages
500 Science
600 Applied science
700 Arts
800 Literature
900 History
000 Generalities
100 Philosophy
200 Religion
300 Social Sciences
400 Languages
500 Science
600 Applied science
700 Arts
800 Literature
900 History
Each of these 10 classes is subdivided into ten more divisions. If we use the 500 (Science) class as an example it is divided like this:
500 Natural sciences
510 Mathematics
520 Astronomy
530 Physics
540 Chemistry
550 Earth sciences
560 Palaeontology
570 Life sciences
580 Botany
590 Zoology
500 Natural sciences
510 Mathematics
520 Astronomy
530 Physics
540 Chemistry
550 Earth sciences
560 Palaeontology
570 Life sciences
580 Botany
590 Zoology
Now each of these divisions is divided again into ten more sections. If we use the 530 (Physics) section as an example it is divided like this:
530 Physics
531 Solid mechanics
532 Fluid mechanics
533 Gas mechanics
534 Sound
535 Light
536 Heat
537 Electricity
538 Magnetism
539 Modern physics
With the use of a decimal point, and extra digits after the point, each of these sections can be further subdivided to cover increasingly narrower subject areas. For example, for Electricity:
530 Physics
531 Solid mechanics
532 Fluid mechanics
533 Gas mechanics
534 Sound
535 Light
536 Heat
537 Electricity
538 Magnetism
539 Modern physics
With the use of a decimal point, and extra digits after the point, each of these sections can be further subdivided to cover increasingly narrower subject areas. For example, for Electricity:
537.534 Radio waves 537.5342 Long waves 537.5343 Short waves The longer the classification number, the more specific the subject is. The shorter the number, the more general it is. So, on the shelves you will find that the more general books come first in the sequence, and as you move along the shelves you will find the books becoming more specialized.
Here is a complete general outline of the Dewey Decimal System.
010 Bibliography 020 Information Science & Librarianship 030 Encyclopedias 040 [Currently unassigned] 050 General serials 060 Organizations 070 Journalism, Publishing 080 General collections 090 Manuscripts, Rare books 100 Philosophy, Psychology 110 Metaphysics 120 Epistemology 130 Parapsychology, Occultism 140 Specific philosophical schools 150 Psychology 160 Logic 170 Ethics 180 Ancient, Medieval, Eastern Philosophy 190 Modern Western philosophy 200 Religion 210 Natural theology 220 Bible 230 Christian theology 240 Moral & devotional theology 250 Christian religious orders 260 Christian social theology 270 Church history 280 Church denominations & sects 290 Other & comparative religions 300 Social sciences 310 General statistics 320 Political science 330 Economics 340 Law 350 Public administration 360 Social services 370 Education 380 Commerce, communications 390 Customs, Folklore 400 Languages 410 Linguistics 420 English, & Old English 430 Germanic languages 440 French 450 Italian 460 Spanish 470 Latin 480 Classical Greek 490 Other languages (including Irish) 500 Natural sciences 510 Mathematics 520 Astronomy 530 Physics 540 Chemistry 550 Earth sciences 560 Paleontology 570 Life sciences 580 Botany 590 Zoology 560 Paleontology 570 Life sciences 600 Technology (Applied sciences) 610 Medical sciences 620 Engineering 630 Agriculture 640 Home economics & family living 650 Management 660 Chemical engineering 670 Manufacturing 680 Manufacturing for specific purposes 690 Buildings & Construction 700 The Arts 710 Civic & landscape art 720 Architecture 730 Sculpture 740 Drawing 750 Painting 760 Graphic arts 770 Photography 780 Music 790 Performing arts & Sports 800 Literature 810 American literature in English 820 English & Old English literature 830 Germanic literature 840 French literature 850 Italian literature 860 Spanish & Portuguese literatures 870 Latin literature 880 Classical Greek literature 890 Literatures of other languages 900 Geography & History 910 Geography & travel 920 Genealogy 930 Ancient history 940 History of Europe 950 History of Asia 960 History of Africa 970 History of North America 980 History of South America 990 History of other areas