The document presents information about the Dewey Decimal Classification system to elementary school students. It discusses that Melvil Dewey created the classification system in 1876 to bring order to the massive amount of world knowledge. The system divides knowledge into 10 main categories represented by 3-digit call numbers that are found on library book spines. The categories include generalities, philosophy, religion, social science, language, science and math, technology, arts, literature, and geography and history.