This article discusses the different classification systems used in libraries. Most libraries categorize books according to the Subject headings. Depending on the type of work, the classification system can be hierarchical or alphabetical. However, it is important to understand the differences between the two systems. In general, the classification systems are organized to help the library staff decide which books are most suitable for their needs. Here are some examples of classification systems.
Subject headings are listed alphabetically
Library subject headings are based on a classification system arranged by the word “subject” or concept. The term is sometimes abbreviated to “subject” and is generally a noun. Subject headings are usually listed alphabetically, but sometimes are arranged according to the same concept. Subject headings are listed in alphabetical order by control number, and some databases use a controlled vocabulary for subject names.
Subdivisions are used to add specificity and depth to subject headings. Sometimes, subdivisions are listed under subject headings in LCSH. Examples of subdivisions are also listed under the heading, such as “subject matter, general science.” The LCSH also lists a variety of headings, including a pattern of accepted subdivisions. These examples are only a small sample of the possible combinations.
While many vocabularies aspire to the same level of classification, the LCSH is the most popular and is used in libraries around the world. It is free and represents subject headings from the Library of Congress, the richest national library in the world. Its extensive machinery allows it to remain a leader in this field. While the Library of Congress’ subject headings system may not be the most convenient, it does make it easier for users to find the right book.
In addition to subject headings, these also have topical and geographic divisions. When headings contain many subdivisions, they should be separated by dashes. Additionally, if you have more than one field for a subject, you can enter parenthetical qualifying information in the subfield (a).
The LCSH list is an exhaustive list of subject concepts used by catalogers. It is the controlled vocabulary for subject concepts. Many other library catalogers use LCSH as well. The purpose of LCSH is to make subject access more convenient for users. Currently, the LCSH lists more than 1 million titles. And this is just a small sample. The full list can take several pages.
Subject headings are divided hierarchically
Subject headings are terms used to describe specific categories of items in the library. While most are simple terms, some are much more complex and involve multiple levels of subdivision. To properly catalog library materials, it is important to have an understanding of subject heading grammar. Here is an overview of the most common subject headings. If you want to make your job easier, read on. This article also discusses how to create your own subject headings.
Geographic subdivisions are terms used to emphasize topic specificity. Geographic subdivisions are names of states, countries, or large cities. For example, a subject heading about bridges in France should be titled France. A geographical subject heading is different from a topical subject heading because it refers to a single unique entity. Therefore, this type of heading is more relevant to works about geography. The following are examples of the use of subject strings in libraries:
Form Headings. These terms describe the physical form of an item. They do not describe the content of the material. They describe the intellectual form of a material, while a form heading describes the physical form. For instance, a book about penguins would be cataloged as “Penguins.” The more specific subject heading will be the one that represents the type of material it is.
The Rule of Three. This rule states that a work may have up to three different subject headings. Therefore, if a work covers reptiles, it would be assigned the Reptiles heading. Likewise, if a book discusses the ethics of oceanography research, it would have a topic heading on oceanography–Ethical aspects. You get the idea. You can also make a compound subject heading with “and” if it is appropriate.
The Sears List subject headings are often followed by a parenthetical phrase, “May subdiv. geog.” This indicates that a particular subject heading may be subdivided geographically. Thus, a work that is relevant to birds in the ocean should not be entered under both Birds and Water birds. The same applies to a book about desert animals and fauna. This method is used to make it easy for people to find the material they are searching for.