Answer:
I hope it is correct!
a) Dewey Decimal System.
The Dewey Decimal System is a system of classification used by libraries to organize and arrange books and other materials on the shelves. It uses a set of numbers to indicate the subject matter of the resource materials, with each number representing a different subject area. This system is widely used in public and school libraries to classify and organize the materials for easy access by patrons. The Dewey Decimal System is named after its inventor Melvil Dewey, who developed it in 1876.