Most academic libraries in the U.S. use the Library of Congress Classification system to organize their collections. Public and school libraries primarily use the Dewey Decimal Classification system.
The classification system is a way to shelve items on the same subject in the same area. Take a look at the Library of Congress (LC) Classification Outline. Look for the blue LC Classification Outline posters in the library to help you with browsing the collections.
Here is the call number of Plants in Hawaiian Medicine by Beatrice H. Krauss.
Notice that there is a period before the author's initial and number. This is a decimal point. It means the numbers on that line are decimal numbers. If two books begin with the same classification number, the smaller decimal number comes first.
When two call numbers start with the same numbers on the first line, which comes first?
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