You shouldn’t include the fourth one
- Some fringing reefs create atolls.
Dewey Decimal is library classification system. It helps to locate books in the library appropriately in order to generate topics by creating library classification system. The Classification helps to organize library materials by field of study. Main divisions are philosophy, social sciences, science, technology, and history. The system is made up of ten classes, each of them divided into ten divisions and which each one has got ten sections. Using Arabic numbers, three whole numbers makes the main classes. Then following numbers make sub-classes and further divisions. The classification is hierarchical and the same hierarchy is used for the system.
