The H-FARM Library adopted the Dewey Decimal Classification (DDC), which is a system that allows libraries to classify their books in order of subject. It was invented by Melvil Dewey in 1876 and is periodically updated by OCLC (Online Computer Library Center).
The Dewey Decimal Code is a numeral shelf mark which follows precise rules, which can be found in OCLC's website: the Introduction to DDC is a brief guide explaining the logic behind the numbers; this guide is then simplified in the DDC Summary, which lists the single shelf markings and the subject they represent.
If you don't know how to put a book back in its place, feel free to ask the librarian!
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