Dewey decimal system

a system used by libraries to classify nonfictional publications into subject categories; the subject is indicated by a three-digit numeral and further specification is given by numerals following a decimal point; publications are shelved by number

図書館でノンフィクション出版物を主題別に分類するために用いられる体系；主題は3桁の数字で示され、小数点以下の数字でさらに細分化される；出版物は番号順に配架される