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Dewey Decimal Help

Help with the Dewey Decimal System

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

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

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:

537.5 Electronics

            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.

000 Generalities

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